Replace functional-index facility with expressional indexes. Any column

of an index can now be a computed expression instead of a simple variable.
Restrictions on expressions are the same as for predicates (only immutable
functions, no sub-selects).  This fixes problems recently introduced with
inlining SQL functions, because the inlining transformation is applied to
both expression trees so the planner can still match them up.  Along the
way, improve efficiency of handling index predicates (both predicates and
index expressions are now cached by the relcache) and fix 7.3 oversight
that didn't record dependencies of predicate expressions.

44 files changed, 1231 insertions, 1172 deletions

diff --git a/src/backend/bootstrap/bootparse.y b/src/backend/bootstrap/bootparse.y
index ee624697776..2f64414aee2 100644
--- a/src/backend/bootstrap/bootparse.y
+++ b/src/backend/bootstrap/bootparse.y
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/bootstrap/bootparse.y,v 1.57 2003/05/27 17:49:45 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/bootstrap/bootparse.y,v 1.58 2003/05/28 16:03:55 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -273,7 +273,7 @@ boot_index_param:
 				{
 					IndexElem *n = makeNode(IndexElem);
 					n->name = LexIDStr($1);
-					n->funcname = n->args = NIL; /* no func indexes */
+					n->expr = NULL;
 					n->opclass = makeList1(makeString(LexIDStr($2)));
 					$$ = n;
 				}
diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c
index c903afaa003..8539537f519 100644
--- a/src/backend/bootstrap/bootstrap.c
+++ b/src/backend/bootstrap/bootstrap.c
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/bootstrap/bootstrap.c,v 1.158 2003/05/27 17:49:45 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/bootstrap/bootstrap.c,v 1.159 2003/05/28 16:03:55 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1169,6 +1169,10 @@ index_register(Oid heap,
 	newind->il_info = (IndexInfo *) palloc(sizeof(IndexInfo));
 
 	memcpy(newind->il_info, indexInfo, sizeof(IndexInfo));
+	/* expressions will likely be null, but may as well copy it */
+	newind->il_info->ii_Expressions = (List *)
+		copyObject(indexInfo->ii_Expressions);
+	newind->il_info->ii_ExpressionsState = NIL;
 	/* predicate will likely be null, but may as well copy it */
 	newind->il_info->ii_Predicate = (List *)
 		copyObject(indexInfo->ii_Predicate);
diff --git a/src/backend/catalog/dependency.c b/src/backend/catalog/dependency.c
index 37282aab7f3..d57f645b281 100644
--- a/src/backend/catalog/dependency.c
+++ b/src/backend/catalog/dependency.c
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/catalog/dependency.c,v 1.24 2003/05/27 17:49:45 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/catalog/dependency.c,v 1.25 2003/05/28 16:03:55 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -851,6 +851,91 @@ recordDependencyOnExpr(const ObjectAddress *depender,
 }
 
 /*
+ * recordDependencyOnSingleRelExpr - find expression dependencies
+ *
+ * As above, but only one relation is expected to be referenced (with
+ * varno = 1 and varlevelsup = 0).  Pass the relation OID instead of a
+ * range table.  An additional frammish is that dependencies on that
+ * relation (or its component columns) will be marked with 'self_behavior',
+ * whereas 'behavior' is used for everything else.
+ */
+void
+recordDependencyOnSingleRelExpr(const ObjectAddress *depender,
+								Node *expr, Oid relId,
+								DependencyType behavior,
+								DependencyType self_behavior)
+{
+	find_expr_references_context context;
+	RangeTblEntry rte;
+
+	init_object_addresses(&context.addrs);
+
+	/* We gin up a rather bogus rangetable list to handle Vars */
+	MemSet(&rte, 0, sizeof(rte));
+	rte.type = T_RangeTblEntry;
+	rte.rtekind = RTE_RELATION;
+	rte.relid = relId;
+
+	context.rtables = makeList1(makeList1(&rte));
+
+	/* Scan the expression tree for referenceable objects */
+	find_expr_references_walker(expr, &context);
+
+	/* Remove any duplicates */
+	eliminate_duplicate_dependencies(&context.addrs);
+
+	/* Separate self-dependencies if necessary */
+	if (behavior != self_behavior && context.addrs.numrefs > 0)
+	{
+		ObjectAddresses self_addrs;
+		ObjectAddress *outobj;
+		int			oldref,
+					outrefs;
+
+		init_object_addresses(&self_addrs);
+
+		outobj = context.addrs.refs;
+		outrefs = 0;
+		for (oldref = 0; oldref < context.addrs.numrefs; oldref++)
+		{
+			ObjectAddress *thisobj = context.addrs.refs + oldref;
+
+			if (thisobj->classId == RelOid_pg_class &&
+				thisobj->objectId == relId)
+			{
+				/* Move this ref into self_addrs */
+				add_object_address(OCLASS_CLASS, relId, thisobj->objectSubId,
+								   &self_addrs);
+			}
+			else
+			{
+				/* Keep it in context.addrs */
+				outobj->classId = thisobj->classId;
+				outobj->objectId = thisobj->objectId;
+				outobj->objectSubId = thisobj->objectSubId;
+				outobj++;
+				outrefs++;
+			}
+		}
+		context.addrs.numrefs = outrefs;
+
+		/* Record the self-dependencies */
+		recordMultipleDependencies(depender,
+								   self_addrs.refs, self_addrs.numrefs,
+								   self_behavior);
+
+		term_object_addresses(&self_addrs);
+	}
+
+	/* Record the external dependencies */
+	recordMultipleDependencies(depender,
+							   context.addrs.refs, context.addrs.numrefs,
+							   behavior);
+
+	term_object_addresses(&context.addrs);
+}
+
+/*
  * Recursively search an expression tree for object references.
  *
  * Note: we avoid creating references to columns of tables that participate
diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c
index 4c9c98e3856..fe57ab7bad3 100644
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/catalog/heap.c,v 1.244 2003/05/12 00:17:02 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/catalog/heap.c,v 1.245 2003/05/28 16:03:55 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -1885,41 +1885,21 @@ RemoveStatistics(Relation rel, AttrNumber attnum)
 static void
 RelationTruncateIndexes(Oid heapId)
 {
-	Relation	indexRelation;
-	ScanKeyData entry;
-	SysScanDesc scan;
-	HeapTuple	indexTuple;
-
-	/* Scan pg_index to find indexes on specified heap */
-	indexRelation = heap_openr(IndexRelationName, AccessShareLock);
-	ScanKeyEntryInitialize(&entry, 0,
-						   Anum_pg_index_indrelid,
-						   F_OIDEQ,
-						   ObjectIdGetDatum(heapId));
-	scan = systable_beginscan(indexRelation, IndexIndrelidIndex, true,
-							  SnapshotNow, 1, &entry);
-
-	while (HeapTupleIsValid(indexTuple = systable_getnext(scan)))
-	{
-		Form_pg_index indexform = (Form_pg_index) GETSTRUCT(indexTuple);
-		Oid			indexId;
-		IndexInfo  *indexInfo;
-		Relation	heapRelation,
-					currentIndex;
+	Relation	heapRelation;
+	List	   *indlist;
 
-		/*
-		 * For each index, fetch info needed for index_build
-		 */
-		indexId = indexform->indexrelid;
-		indexInfo = BuildIndexInfo(indexform);
+	/*
+	 * Open the heap rel.  We need grab no lock because we assume
+	 * heap_truncate is holding an exclusive lock on the heap rel.
+	 */
+	heapRelation = heap_open(heapId, NoLock);
 
-		/*
-		 * We have to re-open the heap rel each time through this loop
-		 * because index_build will close it again.  We need grab no lock,
-		 * however, because we assume heap_truncate is holding an
-		 * exclusive lock on the heap rel.
-		 */
-		heapRelation = heap_open(heapId, NoLock);
+	/* Ask the relcache to produce a list of the indexes of the rel */
+	foreach(indlist, RelationGetIndexList(heapRelation))
+	{
+		Oid			indexId = lfirsto(indlist);
+		Relation	currentIndex;
+		IndexInfo  *indexInfo;
 
 		/* Open the index relation */
 		currentIndex = index_open(indexId);
@@ -1927,6 +1907,9 @@ RelationTruncateIndexes(Oid heapId)
 		/* Obtain exclusive lock on it, just to be sure */
 		LockRelation(currentIndex, AccessExclusiveLock);
 
+		/* Fetch info needed for index_build */
+		indexInfo = BuildIndexInfo(currentIndex);
+
 		/*
 		 * Drop any buffers associated with this index. If they're dirty,
 		 * they're just dropped without bothering to flush to disk.
@@ -1943,13 +1926,14 @@ RelationTruncateIndexes(Oid heapId)
 
 		/*
 		 * index_build will close both the heap and index relations (but
-		 * not give up the locks we hold on them).
+		 * not give up the locks we hold on them).  We're done with this
+		 * index, but we must re-open the heap rel.
 		 */
+		heapRelation = heap_open(heapId, NoLock);
 	}
 
-	/* Complete the scan and close pg_index */
-	systable_endscan(scan);
-	heap_close(indexRelation, AccessShareLock);
+	/* Finish by closing the heap rel again */
+	heap_close(heapRelation, NoLock);
 }
 
 /*
diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index 3533b24ca78..1399f960f71 100644
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/catalog/index.c,v 1.209 2003/02/19 04:06:28 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/catalog/index.c,v 1.210 2003/05/28 16:03:56 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -42,6 +42,7 @@
 #include "miscadmin.h"
 #include "optimizer/clauses.h"
 #include "optimizer/prep.h"
+#include "parser/parse_expr.h"
 #include "parser/parse_func.h"
 #include "storage/sinval.h"
 #include "storage/smgr.h"
@@ -63,11 +64,9 @@
 	((natts) * AVG_ATTR_SIZE + MAXALIGN(sizeof(HeapTupleHeaderData))))
 
 /* non-export function prototypes */
-static TupleDesc BuildFuncTupleDesc(Oid funcOid,
-				   Oid *classObjectId);
 static TupleDesc ConstructTupleDescriptor(Relation heapRelation,
-						 int numatts, AttrNumber *attNums,
-						 Oid *classObjectId);
+										  IndexInfo *indexInfo,
+										  Oid *classObjectId);
 static void UpdateRelationRelation(Relation indexRelation);
 static void InitializeAttributeOids(Relation indexRelation,
 						int numatts, Oid indexoid);
@@ -98,95 +97,18 @@ IsReindexProcessing(void)
 	return reindexing;
 }
 
-static TupleDesc
-BuildFuncTupleDesc(Oid funcOid,
-				   Oid *classObjectId)
-{
-	TupleDesc	funcTupDesc;
-	HeapTuple	tuple;
-	Oid			keyType;
-	Oid			retType;
-	Form_pg_type typeTup;
-
-	/*
-	 * Allocate and zero a tuple descriptor for a one-column tuple.
-	 */
-	funcTupDesc = CreateTemplateTupleDesc(1, false);
-	funcTupDesc->attrs[0] = (Form_pg_attribute) palloc0(ATTRIBUTE_TUPLE_SIZE);
-
-	/*
-	 * Lookup the function to get its name and return type.
-	 */
-	tuple = SearchSysCache(PROCOID,
-						   ObjectIdGetDatum(funcOid),
-						   0, 0, 0);
-	if (!HeapTupleIsValid(tuple))
-		elog(ERROR, "Function %u does not exist", funcOid);
-	retType = ((Form_pg_proc) GETSTRUCT(tuple))->prorettype;
-
-	/*
-	 * make the attributes name the same as the functions
-	 */
-	namestrcpy(&funcTupDesc->attrs[0]->attname,
-			   NameStr(((Form_pg_proc) GETSTRUCT(tuple))->proname));
-
-	ReleaseSysCache(tuple);
-
-	/*
-	 * Check the opclass to see if it provides a keytype (overriding the
-	 * function result type).
-	 */
-	tuple = SearchSysCache(CLAOID,
-						   ObjectIdGetDatum(classObjectId[0]),
-						   0, 0, 0);
-	if (!HeapTupleIsValid(tuple))
-		elog(ERROR, "Opclass %u does not exist", classObjectId[0]);
-	keyType = ((Form_pg_opclass) GETSTRUCT(tuple))->opckeytype;
-	ReleaseSysCache(tuple);
-
-	if (!OidIsValid(keyType))
-		keyType = retType;
-
-	/*
-	 * Lookup the key type in pg_type for the type length etc.
-	 */
-	tuple = SearchSysCache(TYPEOID,
-						   ObjectIdGetDatum(keyType),
-						   0, 0, 0);
-	if (!HeapTupleIsValid(tuple))
-		elog(ERROR, "Type %u does not exist", keyType);
-	typeTup = (Form_pg_type) GETSTRUCT(tuple);
-
-	/*
-	 * Assign some of the attributes values. Leave the rest as 0.
-	 */
-	funcTupDesc->attrs[0]->attnum = 1;
-	funcTupDesc->attrs[0]->atttypid = keyType;
-	funcTupDesc->attrs[0]->attlen = typeTup->typlen;
-	funcTupDesc->attrs[0]->attbyval = typeTup->typbyval;
-	funcTupDesc->attrs[0]->attstorage = typeTup->typstorage;
-	funcTupDesc->attrs[0]->attalign = typeTup->typalign;
-	funcTupDesc->attrs[0]->attcacheoff = -1;
-	funcTupDesc->attrs[0]->atttypmod = -1;
-	funcTupDesc->attrs[0]->attislocal = true;
-
-	ReleaseSysCache(tuple);
-
-	return funcTupDesc;
-}
-
-/* ----------------------------------------------------------------
+/*
  *		ConstructTupleDescriptor
  *
- * Build an index tuple descriptor for a new index (plain not functional)
- * ----------------------------------------------------------------
+ * Build an index tuple descriptor for a new index
  */
 static TupleDesc
 ConstructTupleDescriptor(Relation heapRelation,
-						 int numatts,
-						 AttrNumber *attNums,
+						 IndexInfo *indexInfo,
 						 Oid *classObjectId)
 {
+	int			numatts = indexInfo->ii_NumIndexAttrs;
+	List	   *indexprs = indexInfo->ii_Expressions;
 	TupleDesc	heapTupDesc;
 	TupleDesc	indexTupDesc;
 	int			natts;			/* #atts in heap rel --- for error checks */
@@ -198,69 +120,109 @@ ConstructTupleDescriptor(Relation heapRelation,
 	/*
 	 * allocate the new tuple descriptor
 	 */
-
 	indexTupDesc = CreateTemplateTupleDesc(numatts, false);
 
-	/* ----------------
-	 *	  for each attribute we are indexing, obtain its attribute
-	 *	  tuple form from either the static table of system attribute
-	 *	  tuple forms or the relation tuple descriptor
-	 * ----------------
+	/*
+	 * For simple index columns, we copy the pg_attribute row from the
+	 * parent relation and modify it as necessary.  For expressions we
+	 * have to cons up a pg_attribute row the hard way.
 	 */
 	for (i = 0; i < numatts; i++)
 	{
-		AttrNumber	atnum;		/* attributeNumber[attributeOffset] */
-		Form_pg_attribute from;
+		AttrNumber	atnum = indexInfo->ii_KeyAttrNumbers[i];
 		Form_pg_attribute to;
 		HeapTuple	tuple;
+		Form_pg_type typeTup;
 		Oid			keyType;
 
-		/*
-		 * get the attribute number and make sure it's valid; determine
-		 * which attribute descriptor to copy
-		 */
-		atnum = attNums[i];
+		indexTupDesc->attrs[i] = to =
+			(Form_pg_attribute) palloc0(ATTRIBUTE_TUPLE_SIZE);
 
-		if (!AttrNumberIsForUserDefinedAttr(atnum))
+		if (atnum != 0)
 		{
+			/* Simple index column */
+			Form_pg_attribute from;
+
+			if (atnum < 0)
+			{
+				/*
+				 * here we are indexing on a system attribute (-1...-n)
+				 */
+				from = SystemAttributeDefinition(atnum,
+												 heapRelation->rd_rel->relhasoids);
+			}
+			else
+			{
+				/*
+				 * here we are indexing on a normal attribute (1...n)
+				 */
+				if (atnum > natts)
+					elog(ERROR, "cannot create index: column %d does not exist",
+						 atnum);
+				from = heapTupDesc->attrs[AttrNumberGetAttrOffset(atnum)];
+			}
+
+			/*
+			 * now that we've determined the "from", let's copy the tuple desc
+			 * data...
+			 */
+			memcpy(to, from, ATTRIBUTE_TUPLE_SIZE);
+
 			/*
-			 * here we are indexing on a system attribute (-1...-n)
+			 * Fix the stuff that should not be the same as the underlying
+			 * attr
 			 */
-			from = SystemAttributeDefinition(atnum,
-									   heapRelation->rd_rel->relhasoids);
+			to->attnum = i + 1;
+
+			to->attstattarget = 0;
+			to->attcacheoff = -1;
+			to->attnotnull = false;
+			to->atthasdef = false;
+			to->attislocal = true;
+			to->attinhcount = 0;
 		}
 		else
 		{
+			/* Expressional index */
+			Node	   *indexkey;
+
+			if (indexprs == NIL)
+				elog(ERROR, "too few entries in indexprs list");
+			indexkey = (Node *) lfirst(indexprs);
+			indexprs = lnext(indexprs);
+
 			/*
-			 * here we are indexing on a normal attribute (1...n)
+			 * Make the attribute's name "pg_expresssion_nnn" (maybe think
+			 * of something better later)
 			 */
-			if (atnum > natts)
-				elog(ERROR, "cannot create index: column %d does not exist",
-					 atnum);
+			sprintf(NameStr(to->attname), "pg_expression_%d", i + 1);
 
-			from = heapTupDesc->attrs[AttrNumberGetAttrOffset(atnum)];
-		}
-
-		/*
-		 * now that we've determined the "from", let's copy the tuple desc
-		 * data...
-		 */
-		indexTupDesc->attrs[i] = to =
-			(Form_pg_attribute) palloc(ATTRIBUTE_TUPLE_SIZE);
-		memcpy(to, from, ATTRIBUTE_TUPLE_SIZE);
+			/*
+			 * Lookup the expression type in pg_type for the type length etc.
+			 */
+			keyType = exprType(indexkey);
+			tuple = SearchSysCache(TYPEOID,
+								   ObjectIdGetDatum(keyType),
+								   0, 0, 0);
+			if (!HeapTupleIsValid(tuple))
+				elog(ERROR, "Type %u does not exist", keyType);
+			typeTup = (Form_pg_type) GETSTRUCT(tuple);
 
-		/*
-		 * Fix the stuff that should not be the same as the underlying
-		 * attr
-		 */
-		to->attnum = i + 1;
+			/*
+			 * Assign some of the attributes values. Leave the rest as 0.
+			 */
+			to->attnum = i + 1;
+			to->atttypid = keyType;
+			to->attlen = typeTup->typlen;
+			to->attbyval = typeTup->typbyval;
+			to->attstorage = typeTup->typstorage;
+			to->attalign = typeTup->typalign;
+			to->attcacheoff = -1;
+			to->atttypmod = -1;
+			to->attislocal = true;
 
-		to->attstattarget = 0;
-		to->attcacheoff = -1;
-		to->attnotnull = false;
-		to->atthasdef = false;
-		to->attislocal = true;
-		to->attinhcount = 0;
+			ReleaseSysCache(tuple);
+		}
 
 		/*
 		 * We do not yet have the correct relation OID for the index, so
@@ -284,8 +246,6 @@ ConstructTupleDescriptor(Relation heapRelation,
 		if (OidIsValid(keyType) && keyType != to->atttypid)
 		{
 			/* index value and heap value have different types */
-			Form_pg_type typeTup;
-
 			tuple = SearchSysCache(TYPEOID,
 								   ObjectIdGetDatum(keyType),
 								   0, 0, 0);
@@ -421,6 +381,7 @@ UpdateIndexRelation(Oid indexoid,
 {
 	int16		indkey[INDEX_MAX_KEYS];
 	Oid			indclass[INDEX_MAX_KEYS];
+	Datum		exprsDatum;
 	Datum		predDatum;
 	Datum		values[Natts_pg_index];
 	char		nulls[Natts_pg_index];
@@ -430,20 +391,32 @@ UpdateIndexRelation(Oid indexoid,
 
 	/*
 	 * Copy the index key and opclass info into zero-filled vectors
-	 *
-	 * (zero filling is essential 'cause we don't store the number of
-	 * index columns explicitly in pg_index, which is pretty grotty...)
 	 */
 	MemSet(indkey, 0, sizeof(indkey));
-	for (i = 0; i < indexInfo->ii_NumKeyAttrs; i++)
-		indkey[i] = indexInfo->ii_KeyAttrNumbers[i];
-
 	MemSet(indclass, 0, sizeof(indclass));
 	for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
+	{
+		indkey[i] = indexInfo->ii_KeyAttrNumbers[i];
 		indclass[i] = classOids[i];
+	}
+
+	/*
+	 * Convert the index expressions (if any) to a text datum
+	 */
+	if (indexInfo->ii_Expressions != NIL)
+	{
+		char	   *exprsString;
+
+		exprsString = nodeToString(indexInfo->ii_Expressions);
+		exprsDatum = DirectFunctionCall1(textin,
+										 CStringGetDatum(exprsString));
+		pfree(exprsString);
+	}
+	else
+		exprsDatum = (Datum) 0;
 
 	/*
-	 * Convert the index-predicate (if any) to a text datum
+	 * Convert the index predicate (if any) to a text datum
 	 */
 	if (indexInfo->ii_Predicate != NIL)
 	{
@@ -455,8 +428,7 @@ UpdateIndexRelation(Oid indexoid,
 		pfree(predString);
 	}
 	else
-		predDatum = DirectFunctionCall1(textin,
-										CStringGetDatum(""));
+		predDatum = (Datum) 0;
 
 	/*
 	 * open the system catalog index relation
@@ -470,14 +442,18 @@ UpdateIndexRelation(Oid indexoid,
 
 	values[Anum_pg_index_indexrelid - 1] = ObjectIdGetDatum(indexoid);
 	values[Anum_pg_index_indrelid - 1] = ObjectIdGetDatum(heapoid);
-	values[Anum_pg_index_indproc - 1] = ObjectIdGetDatum(indexInfo->ii_FuncOid);
 	values[Anum_pg_index_indkey - 1] = PointerGetDatum(indkey);
 	values[Anum_pg_index_indclass - 1] = PointerGetDatum(indclass);
-	values[Anum_pg_index_indisclustered - 1] = BoolGetDatum(false);
+	values[Anum_pg_index_indnatts - 1] = Int16GetDatum(indexInfo->ii_NumIndexAttrs);
 	values[Anum_pg_index_indisunique - 1] = BoolGetDatum(indexInfo->ii_Unique);
 	values[Anum_pg_index_indisprimary - 1] = BoolGetDatum(primary);
-	values[Anum_pg_index_indreference - 1] = ObjectIdGetDatum(InvalidOid);
+	values[Anum_pg_index_indisclustered - 1] = BoolGetDatum(false);
+	values[Anum_pg_index_indexprs - 1] = exprsDatum;
+	if (exprsDatum == (Datum) 0)
+		nulls[Anum_pg_index_indexprs - 1] = 'n';
 	values[Anum_pg_index_indpred - 1] = predDatum;
+	if (predDatum == (Datum) 0)
+		nulls[Anum_pg_index_indpred - 1] = 'n';
 
 	tuple = heap_formtuple(RelationGetDescr(pg_index), values, nulls);
 
@@ -538,8 +514,7 @@ index_create(Oid heapRelationId,
 	/*
 	 * check parameters
 	 */
-	if (indexInfo->ii_NumIndexAttrs < 1 ||
-		indexInfo->ii_NumKeyAttrs < 1)
+	if (indexInfo->ii_NumIndexAttrs < 1)
 		elog(ERROR, "must index at least one column");
 
 	if (!allow_system_table_mods &&
@@ -564,16 +539,9 @@ index_create(Oid heapRelationId,
 	/*
 	 * construct tuple descriptor for index tuples
 	 */
-	if (OidIsValid(indexInfo->ii_FuncOid))
-		indexTupDesc = BuildFuncTupleDesc(indexInfo->ii_FuncOid,
-										  classObjectId);
-	else
-		indexTupDesc = ConstructTupleDescriptor(heapRelation,
-												indexInfo->ii_NumKeyAttrs,
-											indexInfo->ii_KeyAttrNumbers,
-												classObjectId);
-
-	indexTupDesc->tdhasoid = false;
+	indexTupDesc = ConstructTupleDescriptor(heapRelation,
+											indexInfo,
+											classObjectId);
 
 	/*
 	 * create the index relation's relcache entry and physical disk file.
@@ -675,6 +643,10 @@ index_create(Oid heapRelationId,
 				constraintType = 0;		/* keep compiler quiet */
 			}
 
+			/* Shouldn't have any expressions */
+			if (indexInfo->ii_Expressions)
+				elog(ERROR, "constraints can't have index expressions");
+
 			conOid = CreateConstraintEntry(indexRelationName,
 										   namespaceId,
 										   constraintType,
@@ -682,7 +654,7 @@ index_create(Oid heapRelationId,
 										   false,		/* isDeferred */
 										   heapRelationId,
 										   indexInfo->ii_KeyAttrNumbers,
-										   indexInfo->ii_NumKeyAttrs,
+										   indexInfo->ii_NumIndexAttrs,
 										   InvalidOid,	/* no domain */
 										   InvalidOid,	/* no foreign key */
 										   NULL,
@@ -703,13 +675,17 @@ index_create(Oid heapRelationId,
 		}
 		else
 		{
-			for (i = 0; i < indexInfo->ii_NumKeyAttrs; i++)
+			/* Create auto dependencies on simply-referenced columns */
+			for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
 			{
-				referenced.classId = RelOid_pg_class;
-				referenced.objectId = heapRelationId;
-				referenced.objectSubId = indexInfo->ii_KeyAttrNumbers[i];
-
-				recordDependencyOn(&myself, &referenced, DEPENDENCY_AUTO);
+				if (indexInfo->ii_KeyAttrNumbers[i] != 0)
+				{
+					referenced.classId = RelOid_pg_class;
+					referenced.objectId = heapRelationId;
+					referenced.objectSubId = indexInfo->ii_KeyAttrNumbers[i];
+
+					recordDependencyOn(&myself, &referenced, DEPENDENCY_AUTO);
+				}
 			}
 		}
 
@@ -723,14 +699,24 @@ index_create(Oid heapRelationId,
 			recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
 		}
 
-		/* Store the dependency on the function (if appropriate) */
-		if (OidIsValid(indexInfo->ii_FuncOid))
+		/* Store dependencies on anything mentioned in index expressions */
+		if (indexInfo->ii_Expressions)
 		{
-			referenced.classId = RelOid_pg_proc;
-			referenced.objectId = indexInfo->ii_FuncOid;
-			referenced.objectSubId = 0;
+			recordDependencyOnSingleRelExpr(&myself,
+											(Node *) indexInfo->ii_Expressions,
+											heapRelationId,
+											DEPENDENCY_NORMAL,
+											DEPENDENCY_AUTO);
+		}
 
-			recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
+		/* Store dependencies on anything mentioned in predicate */
+		if (indexInfo->ii_Predicate)
+		{
+			recordDependencyOnSingleRelExpr(&myself,
+											(Node *) indexInfo->ii_Predicate,
+											heapRelationId,
+											DEPENDENCY_NORMAL,
+											DEPENDENCY_AUTO);
 		}
 	}
 
@@ -864,7 +850,7 @@ index_drop(Oid indexId)
 
 /* ----------------
  *		BuildIndexInfo
- *			Construct an IndexInfo record given the index's pg_index tuple
+ *			Construct an IndexInfo record for an open index
  *
  * IndexInfo stores the information about the index that's needed by
  * FormIndexDatum, which is used for both index_build() and later insertion
@@ -873,62 +859,31 @@ index_drop(Oid indexId)
  * ----------------
  */
 IndexInfo *
-BuildIndexInfo(Form_pg_index indexStruct)
+BuildIndexInfo(Relation index)
 {
 	IndexInfo  *ii = makeNode(IndexInfo);
+	Form_pg_index indexStruct = index->rd_index;
 	int			i;
 	int			numKeys;
 
-	/*
-	 * count the number of keys, and copy them into the IndexInfo
-	 */
-	numKeys = 0;
-	for (i = 0; i < INDEX_MAX_KEYS &&
-		 indexStruct->indkey[i] != InvalidAttrNumber; i++)
-	{
+	/* check the number of keys, and copy attr numbers into the IndexInfo */
+	numKeys = indexStruct->indnatts;
+	if (numKeys < 1 || numKeys > INDEX_MAX_KEYS)
+		elog(ERROR, "invalid indnatts %d for index %u",
+			 numKeys, RelationGetRelid(index));
+	ii->ii_NumIndexAttrs = numKeys;
+	for (i = 0; i < numKeys; i++)
 		ii->ii_KeyAttrNumbers[i] = indexStruct->indkey[i];
-		numKeys++;
-	}
-	ii->ii_NumKeyAttrs = numKeys;
 
-	/*
-	 * Handle functional index.
-	 *
-	 * If we have a functional index then the number of attributes defined in
-	 * the index must be 1 (the function's single return value). Otherwise
-	 * it's same as number of keys.
-	 */
-	ii->ii_FuncOid = indexStruct->indproc;
+	/* fetch any expressions needed for expressional indexes */
+	ii->ii_Expressions = RelationGetIndexExpressions(index);
+	ii->ii_ExpressionsState = NIL;
 
-	if (OidIsValid(indexStruct->indproc))
-	{
-		ii->ii_NumIndexAttrs = 1;
-		/* Do a lookup on the function, too */
-		fmgr_info(indexStruct->indproc, &ii->ii_FuncInfo);
-	}
-	else
-		ii->ii_NumIndexAttrs = numKeys;
-
-	/*
-	 * If partial index, convert predicate into expression nodetree
-	 */
-	if (VARSIZE(&indexStruct->indpred) > VARHDRSZ)
-	{
-		char	   *predString;
-
-		predString = DatumGetCString(DirectFunctionCall1(textout,
-								PointerGetDatum(&indexStruct->indpred)));
-		ii->ii_Predicate = stringToNode(predString);
-		ii->ii_PredicateState = NIL;
-		pfree(predString);
-	}
-	else
-	{
-		ii->ii_Predicate = NIL;
-		ii->ii_PredicateState = NIL;
-	}
+	/* fetch index predicate if any */
+	ii->ii_Predicate = RelationGetIndexPredicate(index);
+	ii->ii_PredicateState = NIL;
 
-	/* Other info */
+	/* other info */
 	ii->ii_Unique = indexStruct->indisunique;
 
 	return ii;
@@ -941,10 +896,14 @@ BuildIndexInfo(Form_pg_index indexStruct)
  *	indexInfo		Info about the index
  *	heapTuple		Heap tuple for which we must prepare an index entry
  *	heapDescriptor	tupledesc for heap tuple
- *	resultCxt		Temporary memory context for any palloc'd datums created
+ *	estate			executor state for evaluating any index expressions
  *	datum			Array of index Datums (output area)
  *	nullv			Array of is-null indicators (output area)
  *
+ * When there are no index expressions, estate may be NULL.  Otherwise it
+ * must be supplied, *and* the ecxt_scantuple slot of its per-tuple expr
+ * context must point to the heap tuple passed in.
+ *
  * For largely historical reasons, we don't actually call index_formtuple()
  * here, we just prepare its input arrays datum[] and nullv[].
  * ----------------
@@ -953,69 +912,58 @@ void
 FormIndexDatum(IndexInfo *indexInfo,
 			   HeapTuple heapTuple,
 			   TupleDesc heapDescriptor,
-			   MemoryContext resultCxt,
+			   EState *estate,
 			   Datum *datum,
 			   char *nullv)
 {
-	MemoryContext oldContext;
+	List	   *indexprs;
 	int			i;
-	Datum		iDatum;
-	bool		isNull;
-
-	oldContext = MemoryContextSwitchTo(resultCxt);
 
-	if (OidIsValid(indexInfo->ii_FuncOid))
+	if (indexInfo->ii_Expressions != NIL &&
+		indexInfo->ii_ExpressionsState == NIL)
 	{
-		/*
-		 * Functional index --- compute the single index attribute
-		 */
-		FunctionCallInfoData fcinfo;
-		bool		anynull = false;
+		/* First time through, set up expression evaluation state */
+		indexInfo->ii_ExpressionsState = (List *)
+			ExecPrepareExpr((Expr *) indexInfo->ii_Expressions,
+							estate);
+		/* Check caller has set up context correctly */
+		Assert(GetPerTupleExprContext(estate)->ecxt_scantuple->val == heapTuple);
+	}
+	indexprs = indexInfo->ii_ExpressionsState;
 
-		MemSet(&fcinfo, 0, sizeof(fcinfo));
-		fcinfo.flinfo = &indexInfo->ii_FuncInfo;
-		fcinfo.nargs = indexInfo->ii_NumKeyAttrs;
+	for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
+	{
+		int			keycol = indexInfo->ii_KeyAttrNumbers[i];
+		Datum		iDatum;
+		bool		isNull;
 
-		for (i = 0; i < indexInfo->ii_NumKeyAttrs; i++)
-		{
-			fcinfo.arg[i] = heap_getattr(heapTuple,
-										 indexInfo->ii_KeyAttrNumbers[i],
-										 heapDescriptor,
-										 &fcinfo.argnull[i]);
-			anynull |= fcinfo.argnull[i];
-		}
-		if (indexInfo->ii_FuncInfo.fn_strict && anynull)
+		if (keycol != 0)
 		{
-			/* force a null result for strict function */
-			iDatum = (Datum) 0;
-			isNull = true;
+			/*
+			 * Plain index column; get the value we need directly from the
+			 * heap tuple.
+			 */
+			iDatum = heap_getattr(heapTuple, keycol, heapDescriptor, &isNull);
 		}
 		else
 		{
-			iDatum = FunctionCallInvoke(&fcinfo);
-			isNull = fcinfo.isnull;
-		}
-		datum[0] = iDatum;
-		nullv[0] = (isNull) ? 'n' : ' ';
-	}
-	else
-	{
-		/*
-		 * Plain index --- for each attribute we need from the heap tuple,
-		 * get the attribute and stick it into the datum and nullv arrays.
-		 */
-		for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
-		{
-			iDatum = heap_getattr(heapTuple,
-								  indexInfo->ii_KeyAttrNumbers[i],
-								  heapDescriptor,
-								  &isNull);
-			datum[i] = iDatum;
-			nullv[i] = (isNull) ? 'n' : ' ';
+			/*
+			 * Index expression --- need to evaluate it.
+			 */
+			if (indexprs == NIL)
+				elog(ERROR, "wrong number of index expressions");
+			iDatum = ExecEvalExprSwitchContext((ExprState *) lfirst(indexprs),
+											   GetPerTupleExprContext(estate),
+											   &isNull,
+											   NULL);
+			indexprs = lnext(indexprs);
 		}
+		datum[i] = iDatum;
+		nullv[i] = (isNull) ? 'n' : ' ';
 	}
 
-	MemoryContextSwitchTo(oldContext);
+	if (indexprs != NIL)
+		elog(ERROR, "wrong number of index expressions");
 }
 
 
@@ -1501,7 +1449,7 @@ IndexBuildHeapScan(Relation heapRelation,
 	heapDescriptor = RelationGetDescr(heapRelation);
 
 	/*
-	 * Need an EState for evaluation of functional-index functions
+	 * Need an EState for evaluation of index expressions
 	 * and partial-index predicates.
 	 */
 	estate = CreateExecutorState();
@@ -1510,9 +1458,9 @@ IndexBuildHeapScan(Relation heapRelation,
 	/*
 	 * If this is a predicate (partial) index, we will need to evaluate
 	 * the predicate using ExecQual, which requires the current tuple to
-	 * be in a slot of a TupleTable.
+	 * be in a slot of a TupleTable.  Likewise if there are any expressions.
 	 */
-	if (indexInfo->ii_Predicate != NIL)
+	if (indexInfo->ii_Predicate != NIL || indexInfo->ii_Expressions != NIL)
 	{
 		tupleTable = ExecCreateTupleTable(1);
 		slot = ExecAllocTableSlot(tupleTable);
@@ -1521,11 +1469,7 @@ IndexBuildHeapScan(Relation heapRelation,
 		/* Arrange for econtext's scan tuple to be the tuple under test */
 		econtext->ecxt_scantuple = slot;
 
-		/*
-		 * Set up execution state for predicate.  Note: we mustn't attempt to
-		 * cache this in the indexInfo, since we're building it in a transient
-		 * EState.
-		 */
+		/* Set up execution state for predicate. */
 		predicate = (List *)
 			ExecPrepareExpr((Expr *) indexInfo->ii_Predicate,
 							estate);
@@ -1676,12 +1620,12 @@ IndexBuildHeapScan(Relation heapRelation,
 		/*
 		 * For the current heap tuple, extract all the attributes we use
 		 * in this index, and note which are null.	This also performs
-		 * evaluation of the function, if this is a functional index.
+		 * evaluation of any expressions needed.
 		 */
 		FormIndexDatum(indexInfo,
 					   heapTuple,
 					   heapDescriptor,
-					   econtext->ecxt_per_tuple_memory,
+					   estate,
 					   attdata,
 					   nulls);
 
@@ -1703,6 +1647,10 @@ IndexBuildHeapScan(Relation heapRelation,
 
 	FreeExecutorState(estate);
 
+	/* These may have been pointing to the now-gone estate */
+	indexInfo->ii_ExpressionsState = NIL;
+	indexInfo->ii_PredicateState = NIL;
+
 	return reltuples;
 }
 
@@ -1807,7 +1755,7 @@ reindex_index(Oid indexId, bool force, bool inplace)
 	}
 
 	/* Fetch info needed for index_build */
-	indexInfo = BuildIndexInfo(iRel->rd_index);
+	indexInfo = BuildIndexInfo(iRel);
 
 	if (inplace)
 	{
diff --git a/src/backend/catalog/indexing.c b/src/backend/catalog/indexing.c
index 27d66b4b2e8..45a60b0e856 100644
--- a/src/backend/catalog/indexing.c
+++ b/src/backend/catalog/indexing.c
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/catalog/indexing.c,v 1.102 2002/09/04 20:31:14 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/catalog/indexing.c,v 1.103 2003/05/28 16:03:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -30,11 +30,9 @@
  * In the current implementation, we share code for opening/closing the
  * indexes with execUtils.c.  But we do not use ExecInsertIndexTuples,
  * because we don't want to create an EState.  This implies that we
- * do not support partial indexes on system catalogs.  Nor do we handle
- * functional indexes very well (the code will work, but will leak memory
- * intraquery, because the index function is called in the per-query context
- * that we are invoked in).  This could be fixed with localized changes here
- * if we wanted to pay the extra overhead of building an EState.
+ * do not support partial or expressional indexes on system catalogs.
+ * This could be fixed with localized changes here if we wanted to pay
+ * the extra overhead of building an EState.
  */
 CatalogIndexState
 CatalogOpenIndexes(Relation heapRel)
@@ -99,7 +97,11 @@ CatalogIndexInsert(CatalogIndexState indstate, HeapTuple heapTuple)
 
 		indexInfo = indexInfoArray[i];
 
-		/* Partial indexes on system catalogs are not supported */
+		/*
+		 * Expressional and partial indexes on system catalogs are not
+		 * supported
+		 */
+		Assert(indexInfo->ii_Expressions == NIL);
 		Assert(indexInfo->ii_Predicate == NIL);
 
 		/*
@@ -109,7 +111,7 @@ CatalogIndexInsert(CatalogIndexState indstate, HeapTuple heapTuple)
 		FormIndexDatum(indexInfo,
 					   heapTuple,
 					   heapDescriptor,
-					   CurrentMemoryContext,
+					   NULL,	/* no expression eval to do */
 					   datum,
 					   nullv);
 
diff --git a/src/backend/catalog/pg_constraint.c b/src/backend/catalog/pg_constraint.c
index e724034969c..3822059dd35 100644
--- a/src/backend/catalog/pg_constraint.c
+++ b/src/backend/catalog/pg_constraint.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/catalog/pg_constraint.c,v 1.12 2002/12/12 20:35:11 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/catalog/pg_constraint.c,v 1.13 2003/05/28 16:03:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -250,18 +250,11 @@ CreateConstraintEntry(const char *constraintName,
 	{
 		/*
 		 * Register dependencies from constraint to objects mentioned in
-		 * CHECK expression.  We gin up a rather bogus rangetable list to
-		 * handle any Vars in the constraint.
+		 * CHECK expression.
 		 */
-		RangeTblEntry rte;
-
-		MemSet(&rte, 0, sizeof(rte));
-		rte.type = T_RangeTblEntry;
-		rte.rtekind = RTE_RELATION;
-		rte.relid = relId;
-
-		recordDependencyOnExpr(&conobject, conExpr, makeList1(&rte),
-							   DEPENDENCY_NORMAL);
+		recordDependencyOnSingleRelExpr(&conobject, conExpr, relId,
+										DEPENDENCY_NORMAL,
+										DEPENDENCY_NORMAL);
 	}
 
 	return conOid;
diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c
index 09ef0ac598e..87062782456 100644
--- a/src/backend/commands/cluster.c
+++ b/src/backend/commands/cluster.c
@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/commands/cluster.c,v 1.109 2003/05/14 03:26:01 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/commands/cluster.c,v 1.110 2003/05/28 16:03:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -214,7 +214,7 @@ cluster(ClusterStmt *stmt)
 
 			/* Start a new transaction for each relation. */
 			StartTransactionCommand();
-			SetQuerySnapshot();	/* might be needed for functional index */
+			SetQuerySnapshot();	/* might be needed for functions in indexes */
 			cluster_rel(rvtc, true);
 			CommitTransactionCommand();
 		}
@@ -320,7 +320,7 @@ cluster_rel(RelToCluster *rvtc, bool recheck)
 	 * seqscan pass over the table to copy the missing rows, but that seems
 	 * expensive and tedious.
 	 */
-	if (VARSIZE(&OldIndex->rd_index->indpred) > VARHDRSZ) /* partial? */
+	if (!heap_attisnull(OldIndex->rd_indextuple, Anum_pg_index_indpred))
 		elog(ERROR, "CLUSTER: cannot cluster on partial index");
 	if (!OldIndex->rd_am->amindexnulls)
 	{
@@ -332,14 +332,24 @@ cluster_rel(RelToCluster *rvtc, bool recheck)
 		 * at the first column; multicolumn-capable AMs are *required* to
 		 * index nulls in columns after the first.
 		 */
-		if (OidIsValid(OldIndex->rd_index->indproc))
-			elog(ERROR, "CLUSTER: cannot cluster on functional index when index access method does not handle nulls");
 		colno = OldIndex->rd_index->indkey[0];
-		if (colno > 0)			/* system columns are non-null */
+		if (colno > 0)
+		{
+			/* ordinary user attribute */
 			if (!OldHeap->rd_att->attrs[colno - 1]->attnotnull)
 				elog(ERROR, "CLUSTER: cannot cluster when index access method does not handle nulls"
 					 "\n\tYou may be able to work around this by marking column \"%s\" NOT NULL",
 					 NameStr(OldHeap->rd_att->attrs[colno - 1]->attname));
+		}
+		else if (colno < 0)
+		{
+			/* system column --- okay, always non-null */
+		}
+		else
+		{
+			/* index expression, lose... */
+			elog(ERROR, "CLUSTER: cannot cluster on expressional index when index access method does not handle nulls");
+		}
 	}
 
 	/*
@@ -557,43 +567,24 @@ get_indexattr_list(Relation OldHeap, Oid OldIndex)
 	foreach(indlist, RelationGetIndexList(OldHeap))
 	{
 		Oid			indexOID = lfirsto(indlist);
-		HeapTuple	indexTuple;
-		HeapTuple	classTuple;
-		Form_pg_index indexForm;
-		Form_pg_class classForm;
+		Relation	oldIndex;
 		IndexAttrs *attrs;
 
-		indexTuple = SearchSysCache(INDEXRELID,
-									ObjectIdGetDatum(indexOID),
-									0, 0, 0);
-		if (!HeapTupleIsValid(indexTuple))
-			elog(ERROR, "Cache lookup failed for index %u", indexOID);
-		indexForm = (Form_pg_index) GETSTRUCT(indexTuple);
-		Assert(indexForm->indexrelid == indexOID);
+		oldIndex = index_open(indexOID);
 
 		attrs = (IndexAttrs *) palloc(sizeof(IndexAttrs));
 		attrs->indexOID = indexOID;
-		attrs->indexInfo = BuildIndexInfo(indexForm);
+		attrs->indexName = pstrdup(NameStr(oldIndex->rd_rel->relname));
+		attrs->accessMethodOID = oldIndex->rd_rel->relam;
+		attrs->indexInfo = BuildIndexInfo(oldIndex);
 		attrs->classOID = (Oid *)
 			palloc(sizeof(Oid) * attrs->indexInfo->ii_NumIndexAttrs);
-		memcpy(attrs->classOID, indexForm->indclass,
+		memcpy(attrs->classOID, oldIndex->rd_index->indclass,
 			   sizeof(Oid) * attrs->indexInfo->ii_NumIndexAttrs);
 		/* We adjust the isclustered attribute to correct new state */
 		attrs->isclustered = (indexOID == OldIndex);
 
-		/* Name and access method of each index come from pg_class */
-		classTuple = SearchSysCache(RELOID,
-									ObjectIdGetDatum(indexOID),
-									0, 0, 0);
-		if (!HeapTupleIsValid(classTuple))
-			elog(ERROR, "Cache lookup failed for index %u", indexOID);
-		classForm = (Form_pg_class) GETSTRUCT(classTuple);
-
-		attrs->indexName = pstrdup(NameStr(classForm->relname));
-		attrs->accessMethodOID = classForm->relam;
-
-		ReleaseSysCache(classTuple);
-		ReleaseSysCache(indexTuple);
+		index_close(oldIndex);
 
 		/*
 		 * Cons the gathered data into the list.  We do not care about
diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c
index 6a371587368..4186a145795 100644
--- a/src/backend/commands/indexcmds.c
+++ b/src/backend/commands/indexcmds.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/commands/indexcmds.c,v 1.99 2003/05/14 03:26:01 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/commands/indexcmds.c,v 1.100 2003/05/28 16:03:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -32,6 +32,7 @@
 #include "optimizer/prep.h"
 #include "parser/parsetree.h"
 #include "parser/parse_coerce.h"
+#include "parser/parse_expr.h"
 #include "parser/parse_func.h"
 #include "utils/acl.h"
 #include "utils/builtins.h"
@@ -39,19 +40,13 @@
 #include "utils/syscache.h"
 
 
-#define IsFuncIndex(ATTR_LIST) (((IndexElem*)lfirst(ATTR_LIST))->funcname != NIL)
-
 /* non-export function prototypes */
-static void CheckPredicate(List *predList, List *rangeTable, Oid baseRelOid);
-static void FuncIndexArgs(IndexInfo *indexInfo, Oid *classOidP,
-			  IndexElem *funcIndex,
-			  Oid relId,
-			  char *accessMethodName, Oid accessMethodId);
-static void NormIndexAttrs(IndexInfo *indexInfo, Oid *classOidP,
+static void CheckPredicate(List *predList);
+static void ComputeIndexAttrs(IndexInfo *indexInfo, Oid *classOidP,
 			   List *attList,
 			   Oid relId,
 			   char *accessMethodName, Oid accessMethodId);
-static Oid GetAttrOpClass(IndexElem *attribute, Oid attrType,
+static Oid GetIndexOpClass(List *opclass, Oid attrType,
 			   char *accessMethodName, Oid accessMethodId);
 static Oid	GetDefaultOpClass(Oid attrType, Oid accessMethodId);
 
@@ -59,8 +54,8 @@ static Oid	GetDefaultOpClass(Oid attrType, Oid accessMethodId);
  * DefineIndex
  *		Creates a new index.
  *
- * 'attributeList' is a list of IndexElem specifying either a functional
- *		index or a list of attributes to index on.
+ * 'attributeList' is a list of IndexElem specifying columns and expressions
+ *		to index on.
  * 'predicate' is the qual specified in the where clause.
  * 'rangetable' is needed to interpret the predicate.
  */
@@ -156,6 +151,16 @@ DefineIndex(RangeVar *heapRelation,
 	ReleaseSysCache(tuple);
 
 	/*
+	 * If a range table was created then check that only the base rel is
+	 * mentioned.
+	 */
+	if (rangetable != NIL)
+	{
+		if (length(rangetable) != 1 || getrelid(1, rangetable) != relationId)
+			elog(ERROR, "index expressions and predicates may refer only to the base relation");
+	}
+
+	/*
 	 * Convert the partial-index predicate from parsetree form to an
 	 * implicit-AND qual expression, for easier evaluation at runtime.
 	 * While we are at it, we reduce it to a canonical (CNF or DNF) form
@@ -164,14 +169,14 @@ DefineIndex(RangeVar *heapRelation,
 	if (predicate)
 	{
 		cnfPred = canonicalize_qual((Expr *) copyObject(predicate), true);
-		CheckPredicate(cnfPred, rangetable, relationId);
+		CheckPredicate(cnfPred);
 	}
 
 	/*
 	 * Check that all of the attributes in a primary key are marked
 	 * as not null, otherwise attempt to ALTER TABLE .. SET NOT NULL
 	 */
-	if (primary && !IsFuncIndex(attributeList))
+	if (primary)
 	{
 		List   *keys;
 
@@ -180,6 +185,9 @@ DefineIndex(RangeVar *heapRelation,
 			IndexElem   *key = (IndexElem *) lfirst(keys);
 			HeapTuple	atttuple;
 
+			if (!key->name)
+				elog(ERROR, "primary keys cannot be expressions");
+
 			/* System attributes are never null, so no problem */
 			if (SystemAttributeByName(key->name, rel->rd_rel->relhasoids))
 				continue;
@@ -216,43 +224,16 @@ DefineIndex(RangeVar *heapRelation,
 	 * structure
 	 */
 	indexInfo = makeNode(IndexInfo);
+	indexInfo->ii_NumIndexAttrs = numberOfAttributes;
+	indexInfo->ii_Expressions = NIL; /* for now */
+	indexInfo->ii_ExpressionsState = NIL;
 	indexInfo->ii_Predicate = cnfPred;
 	indexInfo->ii_PredicateState = NIL;
-	indexInfo->ii_FuncOid = InvalidOid;
 	indexInfo->ii_Unique = unique;
 
-	if (IsFuncIndex(attributeList))
-	{
-		IndexElem  *funcIndex = (IndexElem *) lfirst(attributeList);
-		int			nargs;
-
-		/* Parser should have given us only one list item, but check */
-		if (numberOfAttributes != 1)
-			elog(ERROR, "Functional index can only have one attribute");
-
-		nargs = length(funcIndex->args);
-		if (nargs > INDEX_MAX_KEYS)
-			elog(ERROR, "Index function can take at most %d arguments",
-				 INDEX_MAX_KEYS);
-
-		indexInfo->ii_NumIndexAttrs = 1;
-		indexInfo->ii_NumKeyAttrs = nargs;
-
-		classObjectId = (Oid *) palloc(sizeof(Oid));
-
-		FuncIndexArgs(indexInfo, classObjectId, funcIndex,
+	classObjectId = (Oid *) palloc(numberOfAttributes * sizeof(Oid));
+	ComputeIndexAttrs(indexInfo, classObjectId, attributeList,
 					  relationId, accessMethodName, accessMethodId);
-	}
-	else
-	{
-		indexInfo->ii_NumIndexAttrs = numberOfAttributes;
-		indexInfo->ii_NumKeyAttrs = numberOfAttributes;
-
-		classObjectId = (Oid *) palloc(numberOfAttributes * sizeof(Oid));
-
-		NormIndexAttrs(indexInfo, classObjectId, attributeList,
-					   relationId, accessMethodName, accessMethodId);
-	}
 
 	index_create(relationId, indexRelationName,
 				 indexInfo, accessMethodId, classObjectId,
@@ -271,8 +252,7 @@ DefineIndex(RangeVar *heapRelation,
 
 /*
  * CheckPredicate
- *		Checks that the given list of partial-index predicates refer
- *		(via the given range table) only to the given base relation oid.
+ *		Checks that the given list of partial-index predicates is valid.
  *
  * This used to also constrain the form of the predicate to forms that
  * indxpath.c could do something with.	However, that seems overly
@@ -281,14 +261,9 @@ DefineIndex(RangeVar *heapRelation,
  * any evaluatable predicate will work.  So accept any predicate here
  * (except ones requiring a plan), and let indxpath.c fend for itself.
  */
-
 static void
-CheckPredicate(List *predList, List *rangeTable, Oid baseRelOid)
+CheckPredicate(List *predList)
 {
-	if (length(rangeTable) != 1 || getrelid(1, rangeTable) != baseRelOid)
-		elog(ERROR,
-		 "Partial-index predicates may refer only to the base relation");
-
 	/*
 	 * We don't currently support generation of an actual query plan for a
 	 * predicate, only simple scalar expressions; hence these
@@ -301,119 +276,19 @@ CheckPredicate(List *predList, List *rangeTable, Oid baseRelOid)
 
 	/*
 	 * A predicate using mutable functions is probably wrong, for the same
-	 * reasons that we don't allow a functional index to use one.
+	 * reasons that we don't allow an index expression to use one.
 	 */
 	if (contain_mutable_functions((Node *) predList))
 		elog(ERROR, "Functions in index predicate must be marked IMMUTABLE");
 }
 
-
 static void
-FuncIndexArgs(IndexInfo *indexInfo,
-			  Oid *classOidP,
-			  IndexElem *funcIndex,
-			  Oid relId,
-			  char *accessMethodName,
-			  Oid accessMethodId)
-{
-	Oid			argTypes[FUNC_MAX_ARGS];
-	List	   *arglist;
-	int			nargs = 0;
-	int			i;
-	FuncDetailCode fdresult;
-	Oid			funcid;
-	Oid			rettype;
-	bool		retset;
-	Oid		   *true_typeids;
-
-	/*
-	 * process the function arguments, which are a list of T_String
-	 * (someday ought to allow more general expressions?)
-	 *
-	 * Note caller already checked that list is not too long.
-	 */
-	MemSet(argTypes, 0, sizeof(argTypes));
-
-	foreach(arglist, funcIndex->args)
-	{
-		char	   *arg = strVal(lfirst(arglist));
-		HeapTuple	tuple;
-		Form_pg_attribute att;
-
-		tuple = SearchSysCacheAttName(relId, arg);
-		if (!HeapTupleIsValid(tuple))
-			elog(ERROR, "DefineIndex: column \"%s\" named in key does not exist", arg);
-		att = (Form_pg_attribute) GETSTRUCT(tuple);
-		indexInfo->ii_KeyAttrNumbers[nargs] = att->attnum;
-		argTypes[nargs] = att->atttypid;
-		ReleaseSysCache(tuple);
-		nargs++;
-	}
-
-	/*
-	 * Lookup the function procedure to get its OID and result type.
-	 *
-	 * We rely on parse_func.c to find the correct function in the possible
-	 * presence of binary-compatible types.  However, parse_func may do
-	 * too much: it will accept a function that requires run-time coercion
-	 * of input types, and the executor is not currently set up to support
-	 * that.  So, check to make sure that the selected function has
-	 * exact-match or binary-compatible input types.
-	 */
-	fdresult = func_get_detail(funcIndex->funcname, funcIndex->args,
-							   nargs, argTypes,
-							   &funcid, &rettype, &retset,
-							   &true_typeids);
-	if (fdresult != FUNCDETAIL_NORMAL)
-	{
-		if (fdresult == FUNCDETAIL_AGGREGATE)
-			elog(ERROR, "DefineIndex: functional index may not use an aggregate function");
-		else if (fdresult == FUNCDETAIL_COERCION)
-			elog(ERROR, "DefineIndex: functional index must use a real function, not a type coercion"
-				 "\n\tTry specifying the index opclass you want to use, instead");
-		else
-			func_error("DefineIndex", funcIndex->funcname, nargs, argTypes,
-					   NULL);
-	}
-
-	if (retset)
-		elog(ERROR, "DefineIndex: cannot index on a function returning a set");
-
-	for (i = 0; i < nargs; i++)
-	{
-		if (!IsBinaryCoercible(argTypes[i], true_typeids[i]))
-			func_error("DefineIndex", funcIndex->funcname, nargs, true_typeids,
-					   "Index function must be binary-compatible with table datatype");
-	}
-
-	/*
-	 * Require that the function be marked immutable.  Using a mutable
-	 * function for a functional index is highly questionable, since if
-	 * you aren't going to get the same result for the same data every
-	 * time, it's not clear what the index entries mean at all.
-	 */
-	if (func_volatile(funcid) != PROVOLATILE_IMMUTABLE)
-		elog(ERROR, "DefineIndex: index function must be marked IMMUTABLE");
-
-	/* Process opclass, using func return type as default type */
-
-	classOidP[0] = GetAttrOpClass(funcIndex, rettype,
-								  accessMethodName, accessMethodId);
-
-	/* OK, return results */
-
-	indexInfo->ii_FuncOid = funcid;
-	/* Need to do the fmgr function lookup now, too */
-	fmgr_info(funcid, &indexInfo->ii_FuncInfo);
-}
-
-static void
-NormIndexAttrs(IndexInfo *indexInfo,
-			   Oid *classOidP,
-			   List *attList,	/* list of IndexElem's */
-			   Oid relId,
-			   char *accessMethodName,
-			   Oid accessMethodId)
+ComputeIndexAttrs(IndexInfo *indexInfo,
+				  Oid *classOidP,
+				  List *attList,	/* list of IndexElem's */
+				  Oid relId,
+				  char *accessMethodName,
+				  Oid accessMethodId)
 {
 	List	   *rest;
 	int			attn = 0;
@@ -424,31 +299,75 @@ NormIndexAttrs(IndexInfo *indexInfo,
 	foreach(rest, attList)
 	{
 		IndexElem  *attribute = (IndexElem *) lfirst(rest);
-		HeapTuple	atttuple;
-		Form_pg_attribute attform;
-
-		if (attribute->name == NULL)
-			elog(ERROR, "missing attribute for define index");
-
-		atttuple = SearchSysCacheAttName(relId, attribute->name);
-		if (!HeapTupleIsValid(atttuple))
-			elog(ERROR, "DefineIndex: attribute \"%s\" not found",
-				 attribute->name);
-		attform = (Form_pg_attribute) GETSTRUCT(atttuple);
+		Oid			atttype;
 
-		indexInfo->ii_KeyAttrNumbers[attn] = attform->attnum;
+		if (attribute->name != NULL)
+		{
+			/* Simple index attribute */
+			HeapTuple	atttuple;
+			Form_pg_attribute attform;
+
+			Assert(attribute->expr == NULL);
+			atttuple = SearchSysCacheAttName(relId, attribute->name);
+			if (!HeapTupleIsValid(atttuple))
+				elog(ERROR, "DefineIndex: attribute \"%s\" not found",
+					 attribute->name);
+			attform = (Form_pg_attribute) GETSTRUCT(atttuple);
+			indexInfo->ii_KeyAttrNumbers[attn] = attform->attnum;
+			atttype = attform->atttypid;
+			ReleaseSysCache(atttuple);
+		}
+		else if (attribute->expr && IsA(attribute->expr, Var))
+		{
+			/* Tricky tricky, he wrote (column) ... treat as simple attr */
+			Var	   *var = (Var *) attribute->expr;
 
-		classOidP[attn] = GetAttrOpClass(attribute, attform->atttypid,
-									   accessMethodName, accessMethodId);
+			indexInfo->ii_KeyAttrNumbers[attn] = var->varattno;
+			atttype = get_atttype(relId, var->varattno);
+		}
+		else
+		{
+			/* Index expression */
+			Assert(attribute->expr != NULL);
+			indexInfo->ii_KeyAttrNumbers[attn] = 0;	/* marks expression */
+			indexInfo->ii_Expressions = lappend(indexInfo->ii_Expressions,
+												attribute->expr);
+			atttype = exprType(attribute->expr);
+
+			/*
+			 * We don't currently support generation of an actual query plan
+			 * for an index expression, only simple scalar expressions;
+			 * hence these restrictions.
+			 */
+			if (contain_subplans(attribute->expr))
+				elog(ERROR, "Cannot use subselect in index expression");
+			if (contain_agg_clause(attribute->expr))
+				elog(ERROR, "Cannot use aggregate in index expression");
+
+			/*
+			 * A expression using mutable functions is probably wrong,
+			 * since if you aren't going to get the same result for the same
+			 * data every time, it's not clear what the index entries mean at
+			 * all.
+			 */
+			if (contain_mutable_functions(attribute->expr))
+				elog(ERROR, "Functions in index expression must be marked IMMUTABLE");
+		}
 
-		ReleaseSysCache(atttuple);
+		classOidP[attn] = GetIndexOpClass(attribute->opclass,
+										  atttype,
+										  accessMethodName,
+										  accessMethodId);
 		attn++;
 	}
 }
 
+/*
+ * Resolve possibly-defaulted operator class specification
+ */
 static Oid
-GetAttrOpClass(IndexElem *attribute, Oid attrType,
-			   char *accessMethodName, Oid accessMethodId)
+GetIndexOpClass(List *opclass, Oid attrType,
+				char *accessMethodName, Oid accessMethodId)
 {
 	char	   *schemaname;
 	char	   *opcname;
@@ -456,7 +375,32 @@ GetAttrOpClass(IndexElem *attribute, Oid attrType,
 	Oid			opClassId,
 				opInputType;
 
-	if (attribute->opclass == NIL)
+	/*
+	 * Release 7.0 removed network_ops, timespan_ops, and
+	 * datetime_ops, so we ignore those opclass names
+	 * so the default *_ops is used.  This can be
+	 * removed in some later release.  bjm 2000/02/07
+	 *
+	 * Release 7.1 removes lztext_ops, so suppress that too
+	 * for a while.  tgl 2000/07/30
+	 *
+	 * Release 7.2 renames timestamp_ops to timestamptz_ops,
+	 * so suppress that too for awhile.  I'm starting to
+	 * think we need a better approach.  tgl 2000/10/01
+	 */
+	if (length(opclass) == 1)
+	{
+		char   *claname = strVal(lfirst(opclass));
+
+		if (strcmp(claname, "network_ops") == 0 ||
+			strcmp(claname, "timespan_ops") == 0 ||
+			strcmp(claname, "datetime_ops") == 0 ||
+			strcmp(claname, "lztext_ops") == 0 ||
+			strcmp(claname, "timestamp_ops") == 0)
+			opclass = NIL;
+	}
+
+	if (opclass == NIL)
 	{
 		/* no operator class specified, so find the default */
 		opClassId = GetDefaultOpClass(attrType, accessMethodId);
@@ -473,7 +417,7 @@ GetAttrOpClass(IndexElem *attribute, Oid attrType,
 	 */
 
 	/* deconstruct the name list */
-	DeconstructQualifiedName(attribute->opclass, &schemaname, &opcname);
+	DeconstructQualifiedName(opclass, &schemaname, &opcname);
 
 	if (schemaname)
 	{
@@ -501,7 +445,7 @@ GetAttrOpClass(IndexElem *attribute, Oid attrType,
 
 	if (!HeapTupleIsValid(tuple))
 		elog(ERROR, "DefineIndex: operator class \"%s\" not supported by access method \"%s\"",
-			 NameListToString(attribute->opclass), accessMethodName);
+			 NameListToString(opclass), accessMethodName);
 
 	/*
 	 * Verify that the index operator class accepts this datatype.	Note
@@ -512,7 +456,7 @@ GetAttrOpClass(IndexElem *attribute, Oid attrType,
 
 	if (!IsBinaryCoercible(attrType, opInputType))
 		elog(ERROR, "operator class \"%s\" does not accept data type %s",
-		 NameListToString(attribute->opclass), format_type_be(attrType));
+		 NameListToString(opclass), format_type_be(attrType));
 
 	ReleaseSysCache(tuple);
 
@@ -773,7 +717,7 @@ ReindexDatabase(const char *dbname, bool force, bool all)
 	for (i = 0; i < relcnt; i++)
 	{
 		StartTransactionCommand();
-		SetQuerySnapshot();		/* might be needed for functional index */
+		SetQuerySnapshot();		/* might be needed for functions in indexes */
 		if (reindex_relation(relids[i], force))
 			elog(NOTICE, "relation %u was reindexed", relids[i]);
 		CommitTransactionCommand();
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 5f60ab9cf01..349fb8f3917 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/commands/tablecmds.c,v 1.72 2003/04/29 22:13:08 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/commands/tablecmds.c,v 1.73 2003/05/28 16:03:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1103,6 +1103,7 @@ renameatt(Oid myrelid,
 	Relation	attrelation;
 	HeapTuple	atttup;
 	Form_pg_attribute attform;
+	int			attnum;
 	List	   *indexoidlist;
 	List	   *indexoidscan;
 
@@ -1178,7 +1179,8 @@ renameatt(Oid myrelid,
 			 oldattname);
 	attform = (Form_pg_attribute) GETSTRUCT(atttup);
 
-	if (attform->attnum < 0)
+	attnum = attform->attnum;
+	if (attnum < 0)
 		elog(ERROR, "renameatt: system attribute \"%s\" may not be renamed",
 			 oldattname);
 
@@ -1217,43 +1219,48 @@ renameatt(Oid myrelid,
 	{
 		Oid			indexoid = lfirsto(indexoidscan);
 		HeapTuple	indextup;
+		Form_pg_index indexform;
+		int			i;
 
 		/*
-		 * First check to see if index is a functional index. If so, its
-		 * column name is a function name and shouldn't be renamed here.
+		 * Scan through index columns to see if there's any simple index
+		 * entries for this attribute.  We ignore expressional entries.
 		 */
 		indextup = SearchSysCache(INDEXRELID,
 								  ObjectIdGetDatum(indexoid),
 								  0, 0, 0);
 		if (!HeapTupleIsValid(indextup))
 			elog(ERROR, "renameatt: can't find index id %u", indexoid);
-		if (OidIsValid(((Form_pg_index) GETSTRUCT(indextup))->indproc))
-		{
-			ReleaseSysCache(indextup);
-			continue;
-		}
-		ReleaseSysCache(indextup);
+		indexform = (Form_pg_index) GETSTRUCT(indextup);
 
-		/*
-		 * Okay, look to see if any column name of the index matches the
-		 * old attribute name.
-		 */
-		atttup = SearchSysCacheCopyAttName(indexoid, oldattname);
-		if (!HeapTupleIsValid(atttup))
-			continue;			/* Nope, so ignore it */
+		for (i = 0; i < indexform->indnatts; i++)
+		{
+			if (attnum != indexform->indkey[i])
+				continue;
+			/*
+			 * Found one, rename it.
+			 */
+			atttup = SearchSysCacheCopy(ATTNUM,
+										ObjectIdGetDatum(indexoid),
+										Int16GetDatum(i + 1),
+										0, 0);
+			if (!HeapTupleIsValid(atttup))
+				continue;		/* should we raise an error? */
+			/*
+			 * Update the (copied) attribute tuple.
+			 */
+			namestrcpy(&(((Form_pg_attribute) GETSTRUCT(atttup))->attname),
+					   newattname);
 
-		/*
-		 * Update the (copied) attribute tuple.
-		 */
-		namestrcpy(&(((Form_pg_attribute) GETSTRUCT(atttup))->attname),
-				   newattname);
+			simple_heap_update(attrelation, &atttup->t_self, atttup);
 
-		simple_heap_update(attrelation, &atttup->t_self, atttup);
+			/* keep system catalog indexes current */
+			CatalogUpdateIndexes(attrelation, atttup);
 
-		/* keep system catalog indexes current */
-		CatalogUpdateIndexes(attrelation, atttup);
+			heap_freetuple(atttup);
+		}
 
-		heap_freetuple(atttup);
+		ReleaseSysCache(indextup);
 	}
 
 	freeList(indexoidlist);
@@ -1986,8 +1993,7 @@ AlterTableAlterColumnDropNotNull(Oid myrelid, bool recurse,
 			 * Loop over each attribute in the primary key and see if it
 			 * matches the to-be-altered attribute
 			 */
-			for (i = 0; i < INDEX_MAX_KEYS &&
-				 indexStruct->indkey[i] != InvalidAttrNumber; i++)
+			for (i = 0; i < indexStruct->indnatts; i++)
 			{
 				if (indexStruct->indkey[i] == attnum)
 					elog(ERROR, "ALTER TABLE: Attribute \"%s\" is in a primary key", colName);
@@ -3185,9 +3191,10 @@ transformFkeyGetPrimaryKey(Relation pkrel, Oid *indexOid,
 
 	/*
 	 * Now build the list of PK attributes from the indkey definition
+	 * (we assume a primary key cannot have expressional elements)
 	 */
 	*attnamelist = NIL;
-	for (i = 0; i < INDEX_MAX_KEYS && indexStruct->indkey[i] != 0; i++)
+	for (i = 0; i < indexStruct->indnatts; i++)
 	{
 		int			pkattno = indexStruct->indkey[i];
 
@@ -3241,26 +3248,40 @@ transformFkeyCheckAttrs(Relation pkrel,
 		indexStruct = (Form_pg_index) GETSTRUCT(indexTuple);
 
 		/*
-		 * Must be unique, not a functional index, and not a partial index
+		 * Must have the right number of columns; must be unique and not a
+		 * partial index; forget it if there are any expressions, too
 		 */
-		if (indexStruct->indisunique &&
-			indexStruct->indproc == InvalidOid &&
-			VARSIZE(&indexStruct->indpred) <= VARHDRSZ)
+		if (indexStruct->indnatts == numattrs &&
+			indexStruct->indisunique &&
+			heap_attisnull(indexTuple, Anum_pg_index_indpred) &&
+			heap_attisnull(indexTuple, Anum_pg_index_indexprs))
 		{
-			for (i = 0; i < INDEX_MAX_KEYS && indexStruct->indkey[i] != 0; i++)
-				;
-			if (i == numattrs)
+			/*
+			 * The given attnum list may match the index columns in any
+			 * order.  Check that each list is a subset of the other.
+			 */
+			for (i = 0; i < numattrs; i++)
+			{
+				found = false;
+				for (j = 0; j < numattrs; j++)
+				{
+					if (attnums[i] == indexStruct->indkey[j])
+					{
+						found = true;
+						break;
+					}
+				}
+				if (!found)
+					break;
+			}
+			if (found)
 			{
-				/*
-				 * The given attnum list may match the index columns in any
-				 * order.  Check that each list is a subset of the other.
-				 */
 				for (i = 0; i < numattrs; i++)
 				{
 					found = false;
 					for (j = 0; j < numattrs; j++)
 					{
-						if (attnums[i] == indexStruct->indkey[j])
+						if (attnums[j] == indexStruct->indkey[i])
 						{
 							found = true;
 							break;
@@ -3269,23 +3290,6 @@ transformFkeyCheckAttrs(Relation pkrel,
 					if (!found)
 						break;
 				}
-				if (found)
-				{
-					for (i = 0; i < numattrs; i++)
-					{
-						found = false;
-						for (j = 0; j < numattrs; j++)
-						{
-							if (attnums[j] == indexStruct->indkey[i])
-							{
-								found = true;
-								break;
-							}
-						}
-						if (!found)
-							break;
-					}
-				}
 			}
 		}
 		ReleaseSysCache(indexTuple);
@@ -4020,12 +4024,12 @@ AlterTableCreateToastTable(Oid relOid, bool silent)
 
 	indexInfo = makeNode(IndexInfo);
 	indexInfo->ii_NumIndexAttrs = 2;
-	indexInfo->ii_NumKeyAttrs = 2;
 	indexInfo->ii_KeyAttrNumbers[0] = 1;
 	indexInfo->ii_KeyAttrNumbers[1] = 2;
+	indexInfo->ii_Expressions = NIL;
+	indexInfo->ii_ExpressionsState = NIL;
 	indexInfo->ii_Predicate = NIL;
 	indexInfo->ii_PredicateState = NIL;
-	indexInfo->ii_FuncOid = InvalidOid;
 	indexInfo->ii_Unique = true;
 
 	classObjectId[0] = OID_BTREE_OPS_OID;
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index b5a8f7f3a17..93701b611ed 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -13,7 +13,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.254 2003/05/27 17:49:45 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.255 2003/05/28 16:03:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -304,7 +304,7 @@ vacuum(VacuumStmt *vacstmt)
 			if (vacstmt->vacuum)
 			{
 				StartTransactionCommand();
-				SetQuerySnapshot();	/* might be needed for functional index */
+				SetQuerySnapshot();	/* might be needed for functions in indexes */
 			}
 			else
 				old_context = MemoryContextSwitchTo(anl_context);
@@ -728,7 +728,7 @@ vacuum_rel(Oid relid, VacuumStmt *vacstmt, char expected_relkind)
 
 	/* Begin a transaction for vacuuming this relation */
 	StartTransactionCommand();
-	SetQuerySnapshot();			/* might be needed for functional index */
+	SetQuerySnapshot();			/* might be needed for functions in indexes */
 
 	/*
 	 * Check for user-requested abort.	Note we want this to be inside a
@@ -3028,7 +3028,10 @@ vac_is_partial_index(Relation indrel)
 		return true;
 
 	/* Otherwise, look to see if there's a partial-index predicate */
-	return (VARSIZE(&indrel->rd_index->indpred) > VARHDRSZ);
+	if (!heap_attisnull(indrel->rd_indextuple, Anum_pg_index_indpred))
+		return true;
+
+	return false;
 }
 
 
diff --git a/src/backend/executor/execUtils.c b/src/backend/executor/execUtils.c
index c06d951f91e..ca4ff192f44 100644
--- a/src/backend/executor/execUtils.c
+++ b/src/backend/executor/execUtils.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/executor/execUtils.c,v 1.99 2003/05/05 17:57:47 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/executor/execUtils.c,v 1.100 2003/05/28 16:03:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -706,10 +706,8 @@ ExecOpenIndices(ResultRelInfo *resultRelInfo)
 		if (!indexDesc->rd_am->amconcurrent)
 			LockRelation(indexDesc, AccessExclusiveLock);
 
-		/*
-		 * extract index key information from the index's pg_index tuple
-		 */
-		ii = BuildIndexInfo(indexDesc->rd_index);
+		/* extract index key information from the index's pg_index info */
+		ii = BuildIndexInfo(indexDesc);
 
 		relationDescs[i] = indexDesc;
 		indexInfoArray[i] = ii;
@@ -797,7 +795,7 @@ ExecInsertIndexTuples(TupleTableSlot *slot,
 
 	/*
 	 * We will use the EState's per-tuple context for evaluating
-	 * predicates and functional-index functions (creating it if it's not
+	 * predicates and index expressions (creating it if it's not
 	 * already there).
 	 */
 	econtext = GetPerTupleExprContext(estate);
@@ -844,11 +842,12 @@ ExecInsertIndexTuples(TupleTableSlot *slot,
 		/*
 		 * FormIndexDatum fills in its datum and null parameters with
 		 * attribute information taken from the given heap tuple.
+		 * It also computes any expressions needed.
 		 */
 		FormIndexDatum(indexInfo,
 					   heapTuple,
 					   heapDescriptor,
-					   econtext->ecxt_per_tuple_memory,
+					   estate,
 					   datum,
 					   nullv);
 
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index 1dc79a4dc40..4a5f858d7b0 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -15,7 +15,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/nodes/copyfuncs.c,v 1.250 2003/05/06 00:20:32 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/nodes/copyfuncs.c,v 1.251 2003/05/28 16:03:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1421,8 +1421,7 @@ _copyIndexElem(IndexElem *from)
 	IndexElem  *newnode = makeNode(IndexElem);
 
 	COPY_STRING_FIELD(name);
-	COPY_NODE_FIELD(funcname);
-	COPY_NODE_FIELD(args);
+	COPY_NODE_FIELD(expr);
 	COPY_NODE_FIELD(opclass);
 
 	return newnode;
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index 6b9cac028b9..ff5400f6ee8 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -18,7 +18,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/nodes/equalfuncs.c,v 1.193 2003/05/06 00:20:32 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/nodes/equalfuncs.c,v 1.194 2003/05/28 16:03:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1466,8 +1466,7 @@ static bool
 _equalIndexElem(IndexElem *a, IndexElem *b)
 {
 	COMPARE_STRING_FIELD(name);
-	COMPARE_NODE_FIELD(funcname);
-	COMPARE_NODE_FIELD(args);
+	COMPARE_NODE_FIELD(expr);
 	COMPARE_NODE_FIELD(opclass);
 
 	return true;
diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index 377c6bd2297..a1b238c93cf 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/nodes/outfuncs.c,v 1.205 2003/05/06 00:20:32 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/nodes/outfuncs.c,v 1.206 2003/05/28 16:03:56 tgl Exp $
  *
  * NOTES
  *	  Every node type that can appear in stored rules' parsetrees *must*
@@ -1181,8 +1181,7 @@ _outIndexElem(StringInfo str, IndexElem *node)
 	WRITE_NODE_TYPE("INDEXELEM");
 
 	WRITE_STRING_FIELD(name);
-	WRITE_NODE_FIELD(funcname);
-	WRITE_NODE_FIELD(args);
+	WRITE_NODE_FIELD(expr);
 	WRITE_NODE_FIELD(opclass);
 }
 
diff --git a/src/backend/optimizer/path/indxpath.c b/src/backend/optimizer/path/indxpath.c
index 454e9c92605..9319f8c1474 100644
--- a/src/backend/optimizer/path/indxpath.c
+++ b/src/backend/optimizer/path/indxpath.c
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/optimizer/path/indxpath.c,v 1.141 2003/05/27 17:49:46 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/optimizer/path/indxpath.c,v 1.142 2003/05/28 16:03:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -43,12 +43,8 @@
 
 /*
  * DoneMatchingIndexKeys() - MACRO
- *
- * Formerly this looked at indexkeys, but that's the wrong thing for a
- * functional index.
  */
-#define DoneMatchingIndexKeys(indexkeys, classes) \
-	(classes[0] == InvalidOid)
+#define DoneMatchingIndexKeys(classes)	(classes[0] == InvalidOid)
 
 #define is_indexable_operator(clause,opclass,indexkey_on_left) \
 	(indexable_operator(clause,opclass,indexkey_on_left) != InvalidOid)
@@ -67,14 +63,14 @@ static List *group_clauses_by_indexkey_for_join(RelOptInfo *rel,
 								IndexOptInfo *index,
 								Relids outer_relids,
 								bool isouterjoin);
-static bool match_clause_to_indexkey(RelOptInfo *rel, IndexOptInfo *index,
-									 int indexkey, Oid opclass, Expr *clause);
-static bool match_join_clause_to_indexkey(RelOptInfo *rel, IndexOptInfo *index,
-						 int indexkey, Oid opclass, Expr *clause);
+static bool match_clause_to_indexcol(RelOptInfo *rel, IndexOptInfo *index,
+									 int indexcol, Oid opclass, Expr *clause);
+static bool match_join_clause_to_indexcol(RelOptInfo *rel, IndexOptInfo *index,
+						 int indexcol, Oid opclass, Expr *clause);
 static Oid indexable_operator(Expr *clause, Oid opclass,
 				   bool indexkey_on_left);
 static bool pred_test(List *predicate_list, List *restrictinfo_list,
-		  List *joininfo_list, int relvarno);
+		  List *joininfo_list);
 static bool pred_test_restrict_list(Expr *predicate, List *restrictinfo_list);
 static bool pred_test_recurse_clause(Expr *predicate, Node *clause);
 static bool pred_test_recurse_pred(Expr *predicate, Node *clause);
@@ -83,10 +79,8 @@ static Relids indexable_outerrelids(RelOptInfo *rel, IndexOptInfo *index);
 static Path *make_innerjoin_index_path(Query *root,
 									   RelOptInfo *rel, IndexOptInfo *index,
 									   List *clausegroups);
-static bool match_index_to_operand(int indexkey, Node *operand,
+static bool match_index_to_operand(Node *operand, int indexcol,
 					   RelOptInfo *rel, IndexOptInfo *index);
-static bool function_index_operand(Expr *funcOpnd, RelOptInfo *rel,
-					   IndexOptInfo *index);
 static bool match_special_index_operator(Expr *clause, Oid opclass,
 							 bool indexkey_on_left);
 static List *expand_indexqual_condition(Expr *clause, Oid opclass);
@@ -149,8 +143,7 @@ create_index_paths(Query *root, RelOptInfo *rel)
 		 * predicate test.
 		 */
 		if (index->indpred != NIL)
-			if (!pred_test(index->indpred, restrictinfo_list, joininfo_list,
-						   rel->relid))
+			if (!pred_test(index->indpred, restrictinfo_list, joininfo_list))
 				continue;
 
 		/*
@@ -371,7 +364,6 @@ match_or_subclause_to_indexkey(RelOptInfo *rel,
 							   IndexOptInfo *index,
 							   Expr *clause)
 {
-	int			indexkey = index->indexkeys[0];
 	Oid			opclass = index->classlist[0];
 
 	if (and_clause((Node *) clause))
@@ -380,14 +372,14 @@ match_or_subclause_to_indexkey(RelOptInfo *rel,
 
 		foreach(item, ((BoolExpr *) clause)->args)
 		{
-			if (match_clause_to_indexkey(rel, index, indexkey, opclass,
+			if (match_clause_to_indexcol(rel, index, 0, opclass,
 										 lfirst(item)))
 				return true;
 		}
 		return false;
 	}
 	else
-		return match_clause_to_indexkey(rel, index, indexkey, opclass,
+		return match_clause_to_indexcol(rel, index, 0, opclass,
 										clause);
 }
 
@@ -426,7 +418,7 @@ extract_or_indexqual_conditions(RelOptInfo *rel,
 								Expr *orsubclause)
 {
 	List	   *quals = NIL;
-	int		   *indexkeys = index->indexkeys;
+	int			indexcol = 0;
 	Oid		   *classes = index->classlist;
 
 	/*
@@ -437,7 +429,6 @@ extract_or_indexqual_conditions(RelOptInfo *rel,
 	 */
 	do
 	{
-		int			curIndxKey = indexkeys[0];
 		Oid			curClass = classes[0];
 		List	   *clausegroup = NIL;
 		List	   *item;
@@ -448,16 +439,16 @@ extract_or_indexqual_conditions(RelOptInfo *rel,
 			{
 				Expr	   *subsubclause = (Expr *) lfirst(item);
 
-				if (match_clause_to_indexkey(rel, index,
-											 curIndxKey, curClass,
+				if (match_clause_to_indexcol(rel, index,
+											 indexcol, curClass,
 											 subsubclause))
 					clausegroup = nconc(clausegroup,
 										expand_indexqual_condition(subsubclause,
 																   curClass));
 			}
 		}
-		else if (match_clause_to_indexkey(rel, index,
-										  curIndxKey, curClass,
+		else if (match_clause_to_indexcol(rel, index,
+										  indexcol, curClass,
 										  orsubclause))
 			clausegroup = expand_indexqual_condition(orsubclause, curClass);
 
@@ -471,8 +462,8 @@ extract_or_indexqual_conditions(RelOptInfo *rel,
 			{
 				RestrictInfo *rinfo = (RestrictInfo *) lfirst(item);
 
-				if (match_clause_to_indexkey(rel, index,
-											 curIndxKey, curClass,
+				if (match_clause_to_indexcol(rel, index,
+											 indexcol, curClass,
 											 rinfo->clause))
 					clausegroup = nconc(clausegroup,
 										expand_indexqual_condition(rinfo->clause,
@@ -489,10 +480,10 @@ extract_or_indexqual_conditions(RelOptInfo *rel,
 
 		quals = nconc(quals, clausegroup);
 
-		indexkeys++;
+		indexcol++;
 		classes++;
 
-	} while (!DoneMatchingIndexKeys(indexkeys, classes));
+	} while (!DoneMatchingIndexKeys(classes));
 
 	if (quals == NIL)
 		elog(ERROR, "extract_or_indexqual_conditions: no matching clause");
@@ -531,7 +522,7 @@ group_clauses_by_indexkey(RelOptInfo *rel, IndexOptInfo *index)
 {
 	List	   *clausegroup_list = NIL;
 	List	   *restrictinfo_list = rel->baserestrictinfo;
-	int		   *indexkeys = index->indexkeys;
+	int			indexcol = 0;
 	Oid		   *classes = index->classlist;
 
 	if (restrictinfo_list == NIL)
@@ -539,7 +530,6 @@ group_clauses_by_indexkey(RelOptInfo *rel, IndexOptInfo *index)
 
 	do
 	{
-		int			curIndxKey = indexkeys[0];
 		Oid			curClass = classes[0];
 		List	   *clausegroup = NIL;
 		List	   *i;
@@ -548,9 +538,9 @@ group_clauses_by_indexkey(RelOptInfo *rel, IndexOptInfo *index)
 		{
 			RestrictInfo *rinfo = (RestrictInfo *) lfirst(i);
 
-			if (match_clause_to_indexkey(rel,
+			if (match_clause_to_indexcol(rel,
 										 index,
-										 curIndxKey,
+										 indexcol,
 										 curClass,
 										 rinfo->clause))
 				clausegroup = lappend(clausegroup, rinfo);
@@ -565,10 +555,10 @@ group_clauses_by_indexkey(RelOptInfo *rel, IndexOptInfo *index)
 
 		clausegroup_list = lappend(clausegroup_list, clausegroup);
 
-		indexkeys++;
+		indexcol++;
 		classes++;
 
-	} while (!DoneMatchingIndexKeys(indexkeys, classes));
+	} while (!DoneMatchingIndexKeys(classes));
 
 	return clausegroup_list;
 }
@@ -592,12 +582,11 @@ group_clauses_by_indexkey_for_join(RelOptInfo *rel, IndexOptInfo *index,
 {
 	List	   *clausegroup_list = NIL;
 	bool		jfound = false;
-	int		   *indexkeys = index->indexkeys;
+	int			indexcol = 0;
 	Oid		   *classes = index->classlist;
 
 	do
 	{
-		int			curIndxKey = indexkeys[0];
 		Oid			curClass = classes[0];
 		List	   *clausegroup = NIL;
 		List	   *i;
@@ -619,9 +608,9 @@ group_clauses_by_indexkey_for_join(RelOptInfo *rel, IndexOptInfo *index,
 				if (isouterjoin && rinfo->ispusheddown)
 					continue;
 
-				if (match_join_clause_to_indexkey(rel,
+				if (match_join_clause_to_indexcol(rel,
 												  index,
-												  curIndxKey,
+												  indexcol,
 												  curClass,
 												  rinfo->clause))
 				{
@@ -640,9 +629,9 @@ group_clauses_by_indexkey_for_join(RelOptInfo *rel, IndexOptInfo *index,
 			if (isouterjoin && rinfo->ispusheddown)
 				continue;
 
-			if (match_clause_to_indexkey(rel,
+			if (match_clause_to_indexcol(rel,
 										 index,
-										 curIndxKey,
+										 indexcol,
 										 curClass,
 										 rinfo->clause))
 				clausegroup = lappend(clausegroup, rinfo);
@@ -657,10 +646,10 @@ group_clauses_by_indexkey_for_join(RelOptInfo *rel, IndexOptInfo *index,
 
 		clausegroup_list = lappend(clausegroup_list, clausegroup);
 
-		indexkeys++;
+		indexcol++;
 		classes++;
 
-	} while (!DoneMatchingIndexKeys(indexkeys, classes));
+	} while (!DoneMatchingIndexKeys(classes));
 
 	/* if no join clause was matched then forget it, per comments above */
 	if (!jfound)
@@ -674,15 +663,15 @@ group_clauses_by_indexkey_for_join(RelOptInfo *rel, IndexOptInfo *index,
 
 
 /*
- * match_clause_to_indexkey()
- *	  Determines whether a restriction clause matches a key of an index.
+ * match_clause_to_indexcol()
+ *	  Determines whether a restriction clause matches a column of an index.
  *
  *	  To match, the clause:
  *
  *	  (1)  must be in the form (indexkey op const) or (const op indexkey);
  *		   and
  *	  (2)  must contain an operator which is in the same class as the index
- *		   operator for this key, or is a "special" operator as recognized
+ *		   operator for this column, or is a "special" operator as recognized
  *		   by match_special_index_operator().
  *
  *	  Presently, the executor can only deal with indexquals that have the
@@ -693,7 +682,7 @@ group_clauses_by_indexkey_for_join(RelOptInfo *rel, IndexOptInfo *index,
  *
  * 'rel' is the relation of interest.
  * 'index' is an index on 'rel'.
- * 'indexkey' is a key of 'index'.
+ * 'indexcol' is a column number of 'index' (counting from 0).
  * 'opclass' is the corresponding operator class.
  * 'clause' is the clause to be tested.
  *
@@ -703,9 +692,9 @@ group_clauses_by_indexkey_for_join(RelOptInfo *rel, IndexOptInfo *index,
  * responsibility of higher-level routines to cope with those.
  */
 static bool
-match_clause_to_indexkey(RelOptInfo *rel,
+match_clause_to_indexcol(RelOptInfo *rel,
 						 IndexOptInfo *index,
-						 int indexkey,
+						 int indexcol,
 						 Oid opclass,
 						 Expr *clause)
 {
@@ -725,7 +714,7 @@ match_clause_to_indexkey(RelOptInfo *rel,
 	 *		(indexkey operator constant) or (constant operator indexkey).
 	 * Anything that is a "pseudo constant" expression will do.
 	 */
-	if (match_index_to_operand(indexkey, leftop, rel, index) &&
+	if (match_index_to_operand(leftop, indexcol, rel, index) &&
 		is_pseudo_constant_clause(rightop))
 	{
 		if (is_indexable_operator(clause, opclass, true))
@@ -740,7 +729,7 @@ match_clause_to_indexkey(RelOptInfo *rel,
 		return false;
 	}
 
-	if (match_index_to_operand(indexkey, rightop, rel, index) &&
+	if (match_index_to_operand(rightop, indexcol, rel, index) &&
 		is_pseudo_constant_clause(leftop))
 	{
 		if (is_indexable_operator(clause, opclass, false))
@@ -759,8 +748,8 @@ match_clause_to_indexkey(RelOptInfo *rel,
 }
 
 /*
- * match_join_clause_to_indexkey()
- *	  Determines whether a join clause matches a key of an index.
+ * match_join_clause_to_indexcol()
+ *	  Determines whether a join clause matches a column of an index.
  *
  *	  To match, the clause:
  *
@@ -768,7 +757,7 @@ match_clause_to_indexkey(RelOptInfo *rel,
  *		   where others is an expression involving only vars of the other
  *		   relation(s); and
  *	  (2)  must contain an operator which is in the same class as the index
- *		   operator for this key, or is a "special" operator as recognized
+ *		   operator for this column, or is a "special" operator as recognized
  *		   by match_special_index_operator().
  *
  *	  As above, we must be able to commute the clause to put the indexkey
@@ -781,7 +770,7 @@ match_clause_to_indexkey(RelOptInfo *rel,
  *
  * 'rel' is the relation of interest.
  * 'index' is an index on 'rel'.
- * 'indexkey' is a key of 'index'.
+ * 'indexcol' is a column number of 'index' (counting from 0).
  * 'opclass' is the corresponding operator class.
  * 'clause' is the clause to be tested.
  *
@@ -791,9 +780,9 @@ match_clause_to_indexkey(RelOptInfo *rel,
  * responsibility of higher-level routines to cope with those.
  */
 static bool
-match_join_clause_to_indexkey(RelOptInfo *rel,
+match_join_clause_to_indexcol(RelOptInfo *rel,
 							  IndexOptInfo *index,
-							  int indexkey,
+							  int indexcol,
 							  Oid opclass,
 							  Expr *clause)
 {
@@ -814,7 +803,7 @@ match_join_clause_to_indexkey(RelOptInfo *rel,
 	 * expression that uses none of the indexed relation's vars and
 	 * contains no volatile functions.
 	 */
-	if (match_index_to_operand(indexkey, leftop, rel, index))
+	if (match_index_to_operand(leftop, indexcol, rel, index))
 	{
 		Relids		othervarnos = pull_varnos(rightop);
 		bool		isIndexable;
@@ -827,7 +816,7 @@ match_join_clause_to_indexkey(RelOptInfo *rel,
 		return isIndexable;
 	}
 
-	if (match_index_to_operand(indexkey, rightop, rel, index))
+	if (match_index_to_operand(rightop, indexcol, rel, index))
 	{
 		Relids		othervarnos = pull_varnos(leftop);
 		bool		isIndexable;
@@ -895,8 +884,7 @@ indexable_operator(Expr *clause, Oid opclass, bool indexkey_on_left)
  *	  to CNF format). --Nels, Jan '93
  */
 static bool
-pred_test(List *predicate_list, List *restrictinfo_list, List *joininfo_list,
-		  int relvarno)
+pred_test(List *predicate_list, List *restrictinfo_list, List *joininfo_list)
 {
 	List	   *pred;
 
@@ -919,18 +907,6 @@ pred_test(List *predicate_list, List *restrictinfo_list, List *joininfo_list,
 		return false;			/* no restriction clauses: the test must
 								 * fail */
 
-	/*
-	 * The predicate as stored in the index definition will use varno 1
-	 * for its Vars referencing the indexed relation.  If the indexed
-	 * relation isn't varno 1 in the query, we must adjust the predicate
-	 * to make the Vars match, else equal() won't work.
-	 */
-	if (relvarno != 1)
-	{
-		predicate_list = copyObject(predicate_list);
-		ChangeVarNodes((Node *) predicate_list, 1, relvarno, 0);
-	}
-
 	foreach(pred, predicate_list)
 	{
 		/*
@@ -1320,17 +1296,16 @@ indexable_outerrelids(RelOptInfo *rel, IndexOptInfo *index)
 		{
 			RestrictInfo *rinfo = (RestrictInfo *) lfirst(j);
 			Expr   *clause = rinfo->clause;
-			int	   *indexkeys = index->indexkeys;
+			int		indexcol = 0;
 			Oid	   *classes = index->classlist;
 
 			do
 			{
-				int			curIndxKey = indexkeys[0];
 				Oid			curClass = classes[0];
 
-				if (match_join_clause_to_indexkey(rel,
+				if (match_join_clause_to_indexcol(rel,
 												  index,
-												  curIndxKey,
+												  indexcol,
 												  curClass,
 												  clause))
 				{
@@ -1338,10 +1313,10 @@ indexable_outerrelids(RelOptInfo *rel, IndexOptInfo *index)
 					break;
 				}
 
-				indexkeys++;
+				indexcol++;
 				classes++;
 
-			} while (!DoneMatchingIndexKeys(indexkeys, classes));
+			} while (!DoneMatchingIndexKeys(classes));
 
 			if (match_found)
 				break;
@@ -1611,16 +1586,22 @@ make_innerjoin_index_path(Query *root,
  * match_index_to_operand()
  *	  Generalized test for a match between an index's key
  *	  and the operand on one side of a restriction or join clause.
- *	  Now check for functional indices as well.
+ *
+ * operand: the nodetree to be compared to the index
+ * indexcol: the column number of the index (counting from 0)
+ * rel: the parent relation
+ * index: the index of interest
  */
 static bool
-match_index_to_operand(int indexkey,
-					   Node *operand,
+match_index_to_operand(Node *operand,
+					   int indexcol,
 					   RelOptInfo *rel,
 					   IndexOptInfo *index)
 {
+	int			indkey;
+
 	/*
-	 * Ignore any RelabelType node above the indexkey.	This is needed to
+	 * Ignore any RelabelType node above the operand.	This is needed to
 	 * be able to apply indexscanning in binary-compatible-operator cases.
 	 * Note: we can assume there is at most one RelabelType node;
 	 * eval_const_expressions() will have simplified if more than one.
@@ -1628,77 +1609,52 @@ match_index_to_operand(int indexkey,
 	if (operand && IsA(operand, RelabelType))
 		operand = (Node *) ((RelabelType *) operand)->arg;
 
-	if (index->indproc == InvalidOid)
+	indkey = index->indexkeys[indexcol];
+	if (indkey != 0)
 	{
 		/*
-		 * Simple index.
+		 * Simple index column; operand must be a matching Var.
 		 */
 		if (operand && IsA(operand, Var) &&
 			rel->relid == ((Var *) operand)->varno &&
-			indexkey == ((Var *) operand)->varattno)
+			indkey == ((Var *) operand)->varattno)
 			return true;
-		else
-			return false;
 	}
-
-	/*
-	 * Functional index.
-	 */
-	return function_index_operand((Expr *) operand, rel, index);
-}
-
-static bool
-function_index_operand(Expr *funcOpnd, RelOptInfo *rel, IndexOptInfo *index)
-{
-	FuncExpr   *function;
-	List	   *funcargs;
-	int		   *indexKeys = index->indexkeys;
-	List	   *arg;
-	int			i;
-
-	/*
-	 * sanity check, make sure we know what we're dealing with here.
-	 */
-	if (funcOpnd == NULL || !IsA(funcOpnd, FuncExpr) ||
-		indexKeys == NULL)
-		return false;
-
-	function = (FuncExpr *) funcOpnd;
-	funcargs = function->args;
-
-	if (function->funcid != index->indproc)
-		return false;
-
-	/*----------
-	 * Check that the arguments correspond to the same arguments used to
-	 * create the functional index.  To do this we must check that
-	 *	1. they refer to the right relation.
-	 *	2. the args have the right attr. numbers in the right order.
-	 * We must ignore RelabelType nodes above the argument Vars in order
-	 * to recognize binary-compatible-function cases correctly.
-	 *----------
-	 */
-	i = 0;
-	foreach(arg, funcargs)
+	else
 	{
-		Var		   *var = (Var *) lfirst(arg);
+		/*
+		 * Index expression; find the correct expression.  (This search could
+		 * be avoided, at the cost of complicating all the callers of this
+		 * routine; doesn't seem worth it.)
+		 */
+		List	   *indexprs;
+		int			i;
+		Node	   *indexkey;
 
-		if (var && IsA(var, RelabelType))
-			var = (Var *) ((RelabelType *) var)->arg;
-		if (var == NULL || !IsA(var, Var))
-			return false;
-		if (indexKeys[i] == 0)
-			return false;
-		if (var->varno != rel->relid || var->varattno != indexKeys[i])
-			return false;
+		indexprs = index->indexprs;
+		for (i = 0; i < indexcol; i++)
+		{
+			if (index->indexkeys[i] == 0)
+			{
+				if (indexprs == NIL)
+					elog(ERROR, "wrong number of index expressions");
+				indexprs = lnext(indexprs);
+			}
+		}
+		if (indexprs == NIL)
+			elog(ERROR, "wrong number of index expressions");
+		indexkey = (Node *) lfirst(indexprs);
+		/*
+		 * Does it match the operand?  Again, strip any relabeling.
+		 */
+		if (indexkey && IsA(indexkey, RelabelType))
+			indexkey = (Node *) ((RelabelType *) indexkey)->arg;
 
-		i++;
+		if (equal(indexkey, operand))
+			return true;
 	}
 
-	if (indexKeys[i] != 0)
-		return false;			/* not enough arguments */
-
-	return true;
+	return false;
 }
 
 /****************************************************************************
@@ -1728,7 +1684,7 @@ function_index_operand(Expr *funcOpnd, RelOptInfo *rel, IndexOptInfo *index)
  *
  * Two routines are provided here, match_special_index_operator() and
  * expand_indexqual_conditions().  match_special_index_operator() is
- * just an auxiliary function for match_clause_to_indexkey(); after
+ * just an auxiliary function for match_clause_to_indexcol(); after
  * the latter fails to recognize a restriction opclause's operator
  * as a member of an index's opclass, it asks match_special_index_operator()
  * whether the clause should be considered an indexqual anyway.
@@ -1915,7 +1871,6 @@ List *
 expand_indexqual_conditions(IndexOptInfo *index, List *clausegroups)
 {
 	List	   *resultquals = NIL;
-	int		   *indexkeys = index->indexkeys;
 	Oid		   *classes = index->classlist;
 
 	if (clausegroups == NIL)
@@ -1937,11 +1892,9 @@ expand_indexqual_conditions(IndexOptInfo *index, List *clausegroups)
 
 		clausegroups = lnext(clausegroups);
 
-		indexkeys++;
 		classes++;
 
-	} while (clausegroups != NIL &&
-			 !DoneMatchingIndexKeys(indexkeys, classes));
+	} while (clausegroups != NIL && !DoneMatchingIndexKeys(classes));
 
 	Assert(clausegroups == NIL); /* else more groups than indexkeys... */
 
diff --git a/src/backend/optimizer/path/pathkeys.c b/src/backend/optimizer/path/pathkeys.c
index cf48b7c47bd..f8e4906c13b 100644
--- a/src/backend/optimizer/path/pathkeys.c
+++ b/src/backend/optimizer/path/pathkeys.c
@@ -11,7 +11,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/optimizer/path/pathkeys.c,v 1.48 2003/05/02 19:48:53 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/optimizer/path/pathkeys.c,v 1.49 2003/05/28 16:03:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -636,73 +636,50 @@ build_index_pathkeys(Query *root,
 	List	   *retval = NIL;
 	int		   *indexkeys = index->indexkeys;
 	Oid		   *ordering = index->ordering;
-	PathKeyItem *item;
-	Oid			sortop;
-
-	if (!indexkeys || indexkeys[0] == 0 ||
-		!ordering || ordering[0] == InvalidOid)
-		return NIL;				/* unordered index? */
+	List	   *indexprs = index->indexprs;
 
-	if (index->indproc)
+	while (*ordering != InvalidOid)
 	{
-		/* Functional index: build a representation of the function call */
-		Expr	   *funcnode;
-		List	   *funcargs = NIL;
+		PathKeyItem *item;
+		Oid			sortop;
+		Node	   *indexkey;
+		List	   *cpathkey;
 
 		sortop = *ordering;
 		if (ScanDirectionIsBackward(scandir))
 		{
 			sortop = get_commutator(sortop);
 			if (sortop == InvalidOid)
-				return NIL;		/* oops, no reverse sort operator? */
+				break;			/* oops, no reverse sort operator? */
 		}
 
-		while (*indexkeys != 0)
+		if (*indexkeys != 0)
 		{
-			funcargs = lappend(funcargs,
-							   find_indexkey_var(root, rel, *indexkeys));
-			indexkeys++;
+			/* simple index column */
+			indexkey = (Node *) find_indexkey_var(root, rel, *indexkeys);
 		}
-
-		funcnode = make_funcclause(index->indproc,
-								   get_func_rettype(index->indproc),
-								   false, /* cannot be a set */
-								   COERCE_DONTCARE,	/* to match any user expr */
-								   funcargs);
-
-		/* Make a one-sublist pathkeys list for the function expression */
-		item = makePathKeyItem((Node *) funcnode, sortop);
-		retval = makeList1(make_canonical_pathkey(root, item));
-	}
-	else
-	{
-		/* Normal non-functional index */
-		while (*indexkeys != 0 && *ordering != InvalidOid)
+		else
 		{
-			Var		   *relvar = find_indexkey_var(root, rel, *indexkeys);
-			List	   *cpathkey;
+			/* expression --- assume we need not copy it */
+			if (indexprs == NIL)
+				elog(ERROR, "wrong number of index expressions");
+			indexkey = (Node *) lfirst(indexprs);
+			indexprs = lnext(indexprs);
+		}
 
-			sortop = *ordering;
-			if (ScanDirectionIsBackward(scandir))
-			{
-				sortop = get_commutator(sortop);
-				if (sortop == InvalidOid)
-					break;		/* oops, no reverse sort operator? */
-			}
+		/* OK, make a sublist for this sort key */
+		item = makePathKeyItem(indexkey, sortop);
+		cpathkey = make_canonical_pathkey(root, item);
 
-			/* OK, make a sublist for this sort key */
-			item = makePathKeyItem((Node *) relvar, sortop);
-			cpathkey = make_canonical_pathkey(root, item);
+		/*
+		 * Eliminate redundant ordering info; could happen if query is
+		 * such that index keys are equijoined...
+		 */
+		if (!ptrMember(cpathkey, retval))
+			retval = lappend(retval, cpathkey);
 
-			/*
-			 * Eliminate redundant ordering info; could happen if query is
-			 * such that index keys are equijoined...
-			 */
-			if (!ptrMember(cpathkey, retval))
-				retval = lappend(retval, cpathkey);
-			indexkeys++;
-			ordering++;
-		}
+		indexkeys++;
+		ordering++;
 	}
 
 	return retval;
diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c
index f50eb792811..0d55dd7f8c3 100644
--- a/src/backend/optimizer/plan/createplan.c
+++ b/src/backend/optimizer/plan/createplan.c
@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/optimizer/plan/createplan.c,v 1.142 2003/05/12 00:17:03 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/optimizer/plan/createplan.c,v 1.143 2003/05/28 16:03:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1198,60 +1198,74 @@ fix_indxqual_operand(Node *node, int baserelid, IndexOptInfo *index,
 					 Oid *opclass)
 {
 	/*
-	 * Remove any binary-compatible relabeling of the indexkey
-	 */
-	if (IsA(node, RelabelType))
-		node = (Node *) ((RelabelType *) node)->arg;
-
-	/*
 	 * We represent index keys by Var nodes having the varno of the base
 	 * table but varattno equal to the index's attribute number (index
 	 * column position).  This is a bit hokey ... would be cleaner to use
 	 * a special-purpose node type that could not be mistaken for a
 	 * regular Var.  But it will do for now.
 	 */
-	if (IsA(node, Var))
+	Var		   *result;
+	int			pos;
+	List	   *indexprs;
+
+	/*
+	 * Remove any binary-compatible relabeling of the indexkey
+	 */
+	if (IsA(node, RelabelType))
+		node = (Node *) ((RelabelType *) node)->arg;
+
+	if (IsA(node, Var) &&
+		((Var *) node)->varno == baserelid)
 	{
-		/* If it's a var, find which index key position it occupies */
-		Assert(index->indproc == InvalidOid);
+		/* Try to match against simple index columns */
+		int			varatt = ((Var *) node)->varattno;
 
-		if (((Var *) node)->varno == baserelid)
+		if (varatt != 0)
 		{
-			int			varatt = ((Var *) node)->varattno;
-			int			pos;
-
-			for (pos = 0; pos < index->nkeys; pos++)
+			for (pos = 0; pos < index->ncolumns; pos++)
 			{
 				if (index->indexkeys[pos] == varatt)
 				{
-					Node	   *newnode = copyObject(node);
-
-					((Var *) newnode)->varattno = pos + 1;
+					result = (Var *) copyObject(node);
+					result->varattno = pos + 1;
 					/* return the correct opclass, too */
 					*opclass = index->classlist[pos];
-					return newnode;
+					return (Node *) result;
 				}
 			}
 		}
-
-		/*
-		 * Oops, this Var isn't an indexkey!
-		 */
-		elog(ERROR, "fix_indxqual_operand: var is not index attribute");
 	}
 
-	/*
-	 * Else, it must be a func expression matching a functional index.
-	 * Since we currently only support single-column functional indexes,
-	 * the returned varattno must be 1.
-	 */
-	Assert(index->indproc != InvalidOid);
-	Assert(is_funcclause(node));	/* not a very thorough check, but easy */
-
-	/* classlist[0] is the only class of a functional index */
-	*opclass = index->classlist[0];
+	/* Try to match against index expressions */
+	indexprs = index->indexprs;
+	for (pos = 0; pos < index->ncolumns; pos++)
+	{
+		if (index->indexkeys[pos] == 0)
+		{
+			Node	   *indexkey;
+
+			if (indexprs == NIL)
+				elog(ERROR, "too few entries in indexprs list");
+			indexkey = (Node *) lfirst(indexprs);
+			if (indexkey && IsA(indexkey, RelabelType))
+				indexkey = (Node *) ((RelabelType *) indexkey)->arg;
+			if (equal(node, indexkey))
+			{
+				/* Found a match */
+				result = makeVar(baserelid, pos + 1,
+								 exprType(lfirst(indexprs)), -1,
+								 0);
+				/* return the correct opclass, too */
+				*opclass = index->classlist[pos];
+				return (Node *) result;
+			}
+			indexprs = lnext(indexprs);
+		}
+	}
 
-	return (Node *) makeVar(baserelid, 1, exprType(node), -1, 0);
+	/* Ooops... */
+	elog(ERROR, "fix_indxqual_operand: node is not index attribute");
+	return NULL;				/* keep compiler quiet */
 }
 
 /*
diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c
index c0ffd939cbe..4d51e7ffbc0 100644
--- a/src/backend/optimizer/util/clauses.c
+++ b/src/backend/optimizer/util/clauses.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/optimizer/util/clauses.c,v 1.136 2003/04/29 22:13:09 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/optimizer/util/clauses.c,v 1.137 2003/05/28 16:03:56 tgl Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -133,28 +133,6 @@ get_rightop(Expr *clause)
 }
 
 /*****************************************************************************
- *		FUNCTION clause functions
- *****************************************************************************/
-
-/*
- * make_funcclause
- *	  Creates a function clause given its function info and argument list.
- */
-Expr *
-make_funcclause(Oid funcid, Oid funcresulttype, bool funcretset,
-				CoercionForm funcformat, List *funcargs)
-{
-	FuncExpr   *expr = makeNode(FuncExpr);
-
-	expr->funcid = funcid;
-	expr->funcresulttype = funcresulttype;
-	expr->funcretset = funcretset;
-	expr->funcformat = funcformat;
-	expr->args = funcargs;
-	return (Expr *) expr;
-}
-
-/*****************************************************************************
  *		NOT clause functions
  *****************************************************************************/
 
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index 9ec638a5a43..36223be93fd 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/optimizer/util/plancat.c,v 1.82 2003/05/12 00:17:03 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/optimizer/util/plancat.c,v 1.83 2003/05/28 16:03:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -27,6 +27,7 @@
 #include "optimizer/clauses.h"
 #include "optimizer/plancat.h"
 #include "parser/parsetree.h"
+#include "rewrite/rewriteManip.h"
 #include "utils/builtins.h"
 #include "utils/fmgroids.h"
 #include "utils/lsyscache.h"
@@ -116,78 +117,67 @@ get_relation_info(Oid relationObjectId, RelOptInfo *rel)
 			Relation	indexRelation;
 			Form_pg_index index;
 			IndexOptInfo *info;
+			int			ncolumns;
 			int			i;
 			int16		amorderstrategy;
 
 			/* Extract info from the relation descriptor for the index */
 			indexRelation = index_open(indexoid);
+			index = indexRelation->rd_index;
 
 			info = makeNode(IndexOptInfo);
 
-			/*
-			 * Need to make these arrays large enough to be sure there is room
-			 * for a terminating 0 at the end of each one.
-			 */
-			info->classlist = (Oid *) palloc(sizeof(Oid) * (INDEX_MAX_KEYS + 1));
-			info->indexkeys = (int *) palloc(sizeof(int) * (INDEX_MAX_KEYS + 1));
-			info->ordering = (Oid *) palloc(sizeof(Oid) * (INDEX_MAX_KEYS + 1));
-
-			/* Extract info from the pg_index tuple */
-			index = indexRelation->rd_index;
 			info->indexoid = index->indexrelid;
-			info->indproc = index->indproc; /* functional index ?? */
-			if (VARSIZE(&index->indpred) > VARHDRSZ) /* partial index ?? */
-			{
-				char	   *predString;
+			info->ncolumns = ncolumns = index->indnatts;
 
-				predString = DatumGetCString(DirectFunctionCall1(textout,
-																 PointerGetDatum(&index->indpred)));
-				info->indpred = (List *) stringToNode(predString);
-				pfree(predString);
-			}
-			else
-				info->indpred = NIL;
-			info->unique = index->indisunique;
+			/*
+			 * Need to make classlist and ordering arrays large enough to put
+			 * a terminating 0 at the end of each one.
+			 */
+			info->indexkeys = (int *) palloc(sizeof(int) * ncolumns);
+			info->classlist = (Oid *) palloc0(sizeof(Oid) * (ncolumns + 1));
+			info->ordering = (Oid *) palloc0(sizeof(Oid) * (ncolumns + 1));
 
-			for (i = 0; i < INDEX_MAX_KEYS; i++)
+			for (i = 0; i < ncolumns; i++)
 			{
-				if (index->indclass[i] == (Oid) 0)
-					break;
 				info->classlist[i] = index->indclass[i];
-			}
-			info->classlist[i] = (Oid) 0;
-			info->ncolumns = i;
-
-			for (i = 0; i < INDEX_MAX_KEYS; i++)
-			{
-				if (index->indkey[i] == 0)
-					break;
 				info->indexkeys[i] = index->indkey[i];
 			}
-			info->indexkeys[i] = 0;
-			info->nkeys = i;
 
 			info->relam = indexRelation->rd_rel->relam;
 			info->pages = indexRelation->rd_rel->relpages;
 			info->tuples = indexRelation->rd_rel->reltuples;
 			info->amcostestimate = index_cost_estimator(indexRelation);
-			amorderstrategy = indexRelation->rd_am->amorderstrategy;
 
 			/*
 			 * Fetch the ordering operators associated with the index, if any.
 			 */
-			MemSet(info->ordering, 0, sizeof(Oid) * (INDEX_MAX_KEYS + 1));
+			amorderstrategy = indexRelation->rd_am->amorderstrategy;
 			if (amorderstrategy != 0)
 			{
 				int			oprindex = amorderstrategy - 1;
 
-				for (i = 0; i < info->ncolumns; i++)
+				for (i = 0; i < ncolumns; i++)
 				{
 					info->ordering[i] = indexRelation->rd_operator[oprindex];
 					oprindex += indexRelation->rd_am->amstrategies;
 				}
 			}
 
+			/*
+			 * Fetch the index expressions and predicate, if any.  We must
+			 * modify the copies we obtain from the relcache to have the
+			 * correct varno for the parent relation, so that they match up
+			 * correctly against qual clauses.
+			 */
+			info->indexprs = RelationGetIndexExpressions(indexRelation);
+			info->indpred = RelationGetIndexPredicate(indexRelation);
+			if (info->indexprs && varno != 1)
+				ChangeVarNodes((Node *) info->indexprs, 1, varno, 0);
+			if (info->indpred && varno != 1)
+				ChangeVarNodes((Node *) info->indpred, 1, varno, 0);
+			info->unique = index->indisunique;
+
 			/* initialize cached join info to empty */
 			info->outer_relids = NULL;
 			info->inner_paths = NIL;
@@ -372,15 +362,15 @@ has_unique_index(RelOptInfo *rel, AttrNumber attno)
 		IndexOptInfo *index = (IndexOptInfo *) lfirst(ilist);
 
 		/*
-		 * Note: ignore functional and partial indexes, since they don't
-		 * allow us to conclude that all attr values are distinct. Also, a
-		 * multicolumn unique index doesn't allow us to conclude that just
-		 * the specified attr is unique.
+		 * Note: ignore partial indexes, since they don't allow us to conclude
+		 * that all attr values are distinct.  We don't take any interest in
+		 * expressional indexes either. Also, a multicolumn unique index
+		 * doesn't allow us to conclude that just the specified attr is
+		 * unique.
 		 */
 		if (index->unique &&
-			index->nkeys == 1 &&
+			index->ncolumns == 1 &&
 			index->indexkeys[0] == attno &&
-			index->indproc == InvalidOid &&
 			index->indpred == NIL)
 			return true;
 	}
diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c
index b7fc22c46be..79b36caad75 100644
--- a/src/backend/parser/analyze.c
+++ b/src/backend/parser/analyze.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- *	$Header: /cvsroot/pgsql/src/backend/parser/analyze.c,v 1.271 2003/05/06 00:20:32 tgl Exp $
+ *	$Header: /cvsroot/pgsql/src/backend/parser/analyze.c,v 1.272 2003/05/28 16:03:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1311,8 +1311,7 @@ transformIndexConstraints(ParseState *pstate, CreateStmtContext *cxt)
 			/* OK, add it to the index definition */
 			iparam = makeNode(IndexElem);
 			iparam->name = pstrdup(key);
-			iparam->funcname = NIL;
-			iparam->args = NIL;
+			iparam->expr = NULL;
 			iparam->opclass = NIL;
 			index->indexParams = lappend(index->indexParams, iparam);
 		}
@@ -1386,11 +1385,13 @@ transformIndexConstraints(ParseState *pstate, CreateStmtContext *cxt)
 
 		if (index->idxname == NULL && index->indexParams != NIL)
 		{
-			iparam = lfirst(index->indexParams);
+			iparam = (IndexElem *) lfirst(index->indexParams);
+			/* we should never see an expression item here */
+			Assert(iparam->expr == NULL);
 			index->idxname = CreateIndexName(cxt->relation->relname,
-											 iparam->name ? iparam->name :
-										 strVal(llast(iparam->funcname)),
-											 "key", cxt->alist);
+											 iparam->name,
+											 "key",
+											 cxt->alist);
 		}
 		if (index->idxname == NULL)		/* should not happen */
 			elog(ERROR, "%s: failed to make implicit index name",
@@ -1454,7 +1455,8 @@ static Query *
 transformIndexStmt(ParseState *pstate, IndexStmt *stmt)
 {
 	Query	   *qry;
-	RangeTblEntry *rte;
+	RangeTblEntry *rte = NULL;
+	List	   *l;
 
 	qry = makeNode(Query);
 	qry->commandType = CMD_UTILITY;
@@ -1477,6 +1479,32 @@ transformIndexStmt(ParseState *pstate, IndexStmt *stmt)
 		stmt->whereClause = transformWhereClause(pstate, stmt->whereClause);
 	}
 
+	/* take care of any index expressions */
+	foreach(l, stmt->indexParams)
+	{
+		IndexElem	*ielem = (IndexElem *) lfirst(l);
+
+		if (ielem->expr)
+		{
+			/* Set up rtable as for predicate, see notes above */
+			if (rte == NULL)
+			{
+				rte = addRangeTableEntry(pstate, stmt->relation, NULL,
+										 false, true);
+				/* no to join list, yes to namespace */
+				addRTEtoQuery(pstate, rte, false, true);
+			}
+			ielem->expr = transformExpr(pstate, ielem->expr);
+			/*
+			 * We check only that the result type is legitimate; this is
+			 * for consistency with what transformWhereClause() checks for
+			 * the predicate.  DefineIndex() will make more checks.
+			 */
+			if (expression_returns_set(ielem->expr))
+				elog(ERROR, "index expression may not return a set");
+		}
+	}
+
 	qry->hasSubLinks = pstate->p_hasSubLinks;
 	stmt->rangetable = pstate->p_rtable;
 
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 0a7ae361f49..681738253bb 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.414 2003/05/15 16:35:28 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.415 2003/05/28 16:03:57 tgl Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -210,7 +210,7 @@ static void doNegateFloat(Value *v);
 				oper_argtypes RuleActionList RuleActionMulti
 				opt_column_list columnList opt_name_list
 				sort_clause opt_sort_clause sortby_list index_params
-				index_list name_list from_clause from_list opt_array_bounds
+				name_list from_clause from_list opt_array_bounds
 				qualified_name_list any_name any_name_list
 				any_operator expr_list dotted_name attrs
 				target_list update_target_list insert_column_list
@@ -276,7 +276,7 @@ static void doNegateFloat(Value *v);
 %type <columnref>	columnref
 %type <alias>	alias_clause
 %type <sortgroupby>		sortby
-%type <ielem>	index_elem func_index
+%type <ielem>	index_elem
 %type <node>	table_ref
 %type <jexpr>	joined_table
 %type <range>	relation_expr
@@ -408,7 +408,7 @@ static void doNegateFloat(Value *v);
 %token			UNIONJOIN
 
 /* Special keywords, not in the query language - see the "lex" file */
-%token <str>	IDENT FCONST SCONST NCONST BCONST XCONST Op
+%token <str>	IDENT FCONST SCONST BCONST XCONST Op
 %token <ival>	ICONST PARAM
 
 /* precedence: lowest to highest */
@@ -2932,7 +2932,7 @@ function_with_argtypes:
  *
  *		QUERY:
  *				create index <indexname> on <relname>
- *				  [ using <access> ] "(" (<col> with <op>)+ ")"
+ *				  [ using <access> ] "(" ( <col> [ using <opclass> ] )+ ")"
  *				  [ where <predicate> ]
  *
  *****************************************************************************/
@@ -2958,70 +2958,48 @@ index_opt_unique:
 
 access_method_clause:
 			USING access_method						{ $$ = $2; }
-			/* If btree changes as our default, update pg_get_indexdef() */
 			| /*EMPTY*/								{ $$ = DEFAULT_INDEX_TYPE; }
 		;
 
-index_params:
-			index_list								{ $$ = $1; }
-			| func_index							{ $$ = makeList1($1); }
+index_params:	index_elem							{ $$ = makeList1($1); }
+			| index_params ',' index_elem			{ $$ = lappend($1, $3); }
 		;
 
-index_list:	index_elem								{ $$ = makeList1($1); }
-			| index_list ',' index_elem				{ $$ = lappend($1, $3); }
-		;
-
-func_index: func_name '(' name_list ')' opt_class
+/*
+ * Index attributes can be either simple column references, or arbitrary
+ * expressions in parens.  For backwards-compatibility reasons, we allow
+ * an expression that's just a function call to be written without parens.
+ */
+index_elem:	attr_name opt_class
+				{
+					$$ = makeNode(IndexElem);
+					$$->name = $1;
+					$$->expr = NULL;
+					$$->opclass = $2;
+				}
+			| func_name '(' expr_list ')' opt_class
 				{
+					FuncCall *n = makeNode(FuncCall);
+					n->funcname = $1;
+					n->args = $3;
+					n->agg_star = FALSE;
+					n->agg_distinct = FALSE;
+
 					$$ = makeNode(IndexElem);
 					$$->name = NULL;
-					$$->funcname = $1;
-					$$->args = $3;
+					$$->expr = (Node *)n;
 					$$->opclass = $5;
 				}
-		  ;
-
-index_elem: attr_name opt_class
+			| '(' a_expr ')' opt_class
 				{
 					$$ = makeNode(IndexElem);
-					$$->name = $1;
-					$$->funcname = NIL;
-					$$->args = NIL;
-					$$->opclass = $2;
+					$$->name = NULL;
+					$$->expr = $2;
+					$$->opclass = $4;
 				}
 		;
 
-opt_class:	any_name
-				{
-					/*
-					 * Release 7.0 removed network_ops, timespan_ops, and
-					 * datetime_ops, so we suppress it from being passed to
-					 * the parser so the default *_ops is used.  This can be
-					 * removed in some later release.  bjm 2000/02/07
-					 *
-					 * Release 7.1 removes lztext_ops, so suppress that too
-					 * for a while.  tgl 2000/07/30
-					 *
-					 * Release 7.2 renames timestamp_ops to timestamptz_ops,
-					 * so suppress that too for awhile.  I'm starting to
-					 * think we need a better approach.  tgl 2000/10/01
-					 */
-					if (length($1) == 1)
-					{
-						char   *claname = strVal(lfirst($1));
-
-						if (strcmp(claname, "network_ops") != 0 &&
-							strcmp(claname, "timespan_ops") != 0 &&
-							strcmp(claname, "datetime_ops") != 0 &&
-							strcmp(claname, "lztext_ops") != 0 &&
-							strcmp(claname, "timestamp_ops") != 0)
-							$$ = $1;
-						else
-							$$ = NIL;
-					}
-					else
-						$$ = $1;
-				}
+opt_class:	any_name								{ $$ = $1; }
 			| USING any_name						{ $$ = $2; }
 			| /*EMPTY*/								{ $$ = NIL; }
 		;
diff --git a/src/backend/tcop/pquery.c b/src/backend/tcop/pquery.c
index 7a66a9095e4..1cad3ec31a3 100644
--- a/src/backend/tcop/pquery.c
+++ b/src/backend/tcop/pquery.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/tcop/pquery.c,v 1.65 2003/05/27 17:49:46 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/tcop/pquery.c,v 1.66 2003/05/28 16:03:58 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -713,8 +713,9 @@ PortalRunUtility(Portal portal, Query *query,
 	 * without freezing a snapshot.  By extension we allow SHOW
 	 * not to set a snapshot.  The other stmts listed are just
 	 * efficiency hacks.  Beware of listing anything that can
-	 * modify the database --- if, say, it has to update a
-	 * functional index, then it had better have a snapshot.
+	 * modify the database --- if, say, it has to update an
+	 * index with expressions that invoke user-defined functions,
+	 * then it had better have a snapshot.
 	 */
 	if (! (IsA(utilityStmt, TransactionStmt) ||
 		   IsA(utilityStmt, LockStmt) ||
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index e41d3245818..1040ff3e238 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -3,7 +3,7 @@
  *				back to source text
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/ruleutils.c,v 1.140 2003/05/20 20:35:10 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/ruleutils.c,v 1.141 2003/05/28 16:03:59 tgl Exp $
  *
  *	  This software is copyrighted by Jan Wieck - Hamburg.
  *
@@ -535,12 +535,14 @@ pg_get_indexdef(PG_FUNCTION_ARGS)
 	Form_pg_index idxrec;
 	Form_pg_class idxrelrec;
 	Form_pg_am	amrec;
+	List	   *indexprs;
+	List	   *context;
 	Oid			indrelid;
 	int			len;
 	int			keyno;
-	Oid			keycoltypes[INDEX_MAX_KEYS];
+	Oid			keycoltype;
 	StringInfoData buf;
-	StringInfoData keybuf;
+	char	   *str;
 	char	   *sep;
 
 	/*
@@ -577,6 +579,30 @@ pg_get_indexdef(PG_FUNCTION_ARGS)
 	amrec = (Form_pg_am) GETSTRUCT(ht_am);
 
 	/*
+	 * Get the index expressions, if any.  (NOTE: we do not use the relcache
+	 * versions of the expressions and predicate, because we want to display
+	 * non-const-folded expressions.)
+	 */
+	if (!heap_attisnull(ht_idx, Anum_pg_index_indexprs))
+	{
+		Datum		exprsDatum;
+		bool		isnull;
+		char	   *exprsString;
+
+		exprsDatum = SysCacheGetAttr(INDEXRELID, ht_idx,
+									 Anum_pg_index_indexprs, &isnull);
+		Assert(!isnull);
+		exprsString = DatumGetCString(DirectFunctionCall1(textout,
+														  exprsDatum));
+		indexprs = (List *) stringToNode(exprsString);
+		pfree(exprsString);
+	}
+	else
+		indexprs = NIL;
+
+	context = deparse_context_for(get_rel_name(indrelid), indrelid);
+
+	/*
 	 * Start the index definition.	Note that the index's name should
 	 * never be schema-qualified, but the indexed rel's name may be.
 	 */
@@ -588,76 +614,72 @@ pg_get_indexdef(PG_FUNCTION_ARGS)
 					 quote_identifier(NameStr(amrec->amname)));
 
 	/*
-	 * Collect the indexed attributes in keybuf
+	 * Report the indexed attributes
 	 */
-	initStringInfo(&keybuf);
 	sep = "";
-	for (keyno = 0; keyno < INDEX_MAX_KEYS; keyno++)
+	for (keyno = 0; keyno < idxrec->indnatts; keyno++)
 	{
 		AttrNumber	attnum = idxrec->indkey[keyno];
-		char	   *attname;
-
-		if (attnum == InvalidAttrNumber)
-			break;
-
-		attname = get_relid_attribute_name(indrelid, attnum);
-		keycoltypes[keyno] = get_atttype(indrelid, attnum);
 
-		appendStringInfo(&keybuf, sep);
+		appendStringInfo(&buf, sep);
 		sep = ", ";
 
-		/*
-		 * Add the indexed field name
-		 */
-		appendStringInfo(&keybuf, "%s", quote_identifier(attname));
+		if (attnum != 0)
+		{
+			/* Simple index column */
+			char	   *attname;
 
-		/*
-		 * If not a functional index, add the operator class name
-		 */
-		if (idxrec->indproc == InvalidOid)
-			get_opclass_name(idxrec->indclass[keyno],
-							 keycoltypes[keyno],
-							 &keybuf);
-	}
+			attname = get_relid_attribute_name(indrelid, attnum);
+			appendStringInfo(&buf, "%s", quote_identifier(attname));
+			keycoltype = get_atttype(indrelid, attnum);
+		}
+		else
+		{
+			/* expressional index */
+			Node	   *indexkey;
+
+			if (indexprs == NIL)
+				elog(ERROR, "too few entries in indexprs list");
+			indexkey = (Node *) lfirst(indexprs);
+			indexprs = lnext(indexprs);
+			/* Deparse */
+			str = deparse_expression(indexkey, context, false, false);
+			/* Need parens if it's not a bare function call */
+			if (indexkey && IsA(indexkey, FuncExpr) &&
+				((FuncExpr *) indexkey)->funcformat == COERCE_EXPLICIT_CALL)
+				appendStringInfo(&buf, "%s", str);
+			else
+				appendStringInfo(&buf, "(%s)", str);
+			keycoltype = exprType(indexkey);
+		}
 
-	if (idxrec->indproc != InvalidOid)
-	{
 		/*
-		 * For functional index say 'func (attrs) opclass'
+		 * Add the operator class name
 		 */
-		appendStringInfo(&buf, "%s(%s)",
-						 generate_function_name(idxrec->indproc,
-												keyno, keycoltypes),
-						 keybuf.data);
-		get_opclass_name(idxrec->indclass[0],
-						 get_func_rettype(idxrec->indproc),
+		get_opclass_name(idxrec->indclass[keyno], keycoltype,
 						 &buf);
 	}
-	else
-	{
-		/*
-		 * Otherwise say 'attr opclass [, ...]'
-		 */
-		appendStringInfo(&buf, "%s", keybuf.data);
-	}
 
 	appendStringInfoChar(&buf, ')');
 
 	/*
 	 * If it's a partial index, decompile and append the predicate
 	 */
-	if (VARSIZE(&idxrec->indpred) > VARHDRSZ)
+	if (!heap_attisnull(ht_idx, Anum_pg_index_indpred))
 	{
 		Node	   *node;
-		List	   *context;
-		char	   *exprstr;
-		char	   *str;
+		Datum		predDatum;
+		bool		isnull;
+		char	   *predString;
 
-		/* Convert TEXT object to C string */
-		exprstr = DatumGetCString(DirectFunctionCall1(textout,
-									 PointerGetDatum(&idxrec->indpred)));
-		/* Convert expression to node tree */
-		node = (Node *) stringToNode(exprstr);
+		/* Convert text string to node tree */
+		predDatum = SysCacheGetAttr(INDEXRELID, ht_idx,
+									Anum_pg_index_indpred, &isnull);
+		Assert(!isnull);
+		predString = DatumGetCString(DirectFunctionCall1(textout,
+														 predDatum));
+		node = (Node *) stringToNode(predString);
+		pfree(predString);
 
 		/*
 		 * If top level is a List, assume it is an implicit-AND structure,
@@ -667,7 +689,6 @@ pg_get_indexdef(PG_FUNCTION_ARGS)
 		if (node && IsA(node, List))
 			node = (Node *) make_ands_explicit((List *) node);
 		/* Deparse */
-		context = deparse_context_for(get_rel_name(indrelid), indrelid);
 		str = deparse_expression(node, context, false, false);
 		appendStringInfo(&buf, " WHERE %s", str);
 	}
@@ -681,7 +702,6 @@ pg_get_indexdef(PG_FUNCTION_ARGS)
 	memcpy(VARDATA(indexdef), buf.data, buf.len);
 
 	pfree(buf.data);
-	pfree(keybuf.data);
 
 	ReleaseSysCache(ht_idx);
 	ReleaseSysCache(ht_idxrel);
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c
index 77ef33b8783..724503e9c4c 100644
--- a/src/backend/utils/adt/selfuncs.c
+++ b/src/backend/utils/adt/selfuncs.c
@@ -15,7 +15,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/selfuncs.c,v 1.138 2003/05/26 00:11:27 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/selfuncs.c,v 1.139 2003/05/28 16:03:59 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -3905,14 +3905,13 @@ btcostestimate(PG_FUNCTION_ARGS)
 						indexSelectivity, indexCorrelation);
 
 	/*
-	 * If it's a functional index, leave the default zero-correlation
-	 * estimate in place.  If not, and if we can get an estimate for the
-	 * first variable's ordering correlation C from pg_statistic, estimate
+	 * If the first column is a simple variable, and we can get an estimate
+	 * for its ordering correlation C from pg_statistic, estimate
 	 * the index correlation as C / number-of-columns. (The idea here is
 	 * that multiple columns dilute the importance of the first column's
 	 * ordering, but don't negate it entirely.)
 	 */
-	if (index->indproc == InvalidOid)
+	if (index->indexkeys[0] != 0)
 	{
 		Oid			relid;
 		HeapTuple	tuple;
@@ -3942,8 +3941,7 @@ btcostestimate(PG_FUNCTION_ARGS)
 
 				Assert(nnumbers == 1);
 				varCorrelation = numbers[0];
-				for (nKeys = 1; index->indexkeys[nKeys] != 0; nKeys++)
-					 /* skip */ ;
+				nKeys = index->ncolumns;
 
 				*indexCorrelation = varCorrelation / nKeys;
 
diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index 6ab9427dfdb..14899e2968b 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/cache/relcache.c,v 1.184 2003/02/09 06:56:28 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/cache/relcache.c,v 1.185 2003/05/28 16:03:59 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -52,6 +52,8 @@
 #include "catalog/pg_type.h"
 #include "commands/trigger.h"
 #include "miscadmin.h"
+#include "optimizer/clauses.h"
+#include "optimizer/planmain.h"
 #include "storage/smgr.h"
 #include "utils/builtins.h"
 #include "utils/catcache.h"
@@ -939,10 +941,9 @@ void
 RelationInitIndexAccessInfo(Relation relation)
 {
 	HeapTuple	tuple;
-	Size		iformsize;
-	Form_pg_index iform;
 	Form_pg_am	aform;
 	MemoryContext indexcxt;
+	MemoryContext oldcontext;
 	IndexStrategy strategy;
 	Oid		   *operator;
 	RegProcedure *support;
@@ -952,8 +953,9 @@ RelationInitIndexAccessInfo(Relation relation)
 	uint16		amsupport;
 
 	/*
-	 * Make a copy of the pg_index entry for the index.  Note that this is
-	 * a variable-length tuple.
+	 * Make a copy of the pg_index entry for the index.  Since pg_index
+	 * contains variable-length and possibly-null fields, we have to do
+	 * this honestly rather than just treating it as a Form_pg_index struct.
 	 */
 	tuple = SearchSysCache(INDEXRELID,
 						   ObjectIdGetDatum(RelationGetRelid(relation)),
@@ -961,11 +963,11 @@ RelationInitIndexAccessInfo(Relation relation)
 	if (!HeapTupleIsValid(tuple))
 		elog(ERROR, "RelationInitIndexAccessInfo: no pg_index entry for index %u",
 			 RelationGetRelid(relation));
-	iformsize = tuple->t_len - tuple->t_data->t_hoff;
-	iform = (Form_pg_index) MemoryContextAlloc(CacheMemoryContext, iformsize);
-	memcpy(iform, GETSTRUCT(tuple), iformsize);
+	oldcontext = MemoryContextSwitchTo(CacheMemoryContext);
+	relation->rd_indextuple = heap_copytuple(tuple);
+	relation->rd_index = (Form_pg_index) GETSTRUCT(relation->rd_indextuple);
+	MemoryContextSwitchTo(oldcontext);
 	ReleaseSysCache(tuple);
-	relation->rd_index = iform;
 
 	/*
 	 * Make a copy of the pg_am entry for the index's access method
@@ -982,6 +984,9 @@ RelationInitIndexAccessInfo(Relation relation)
 	relation->rd_am = aform;
 
 	natts = relation->rd_rel->relnatts;
+	if (natts != relation->rd_index->indnatts)
+		elog(ERROR, "RelationInitIndexAccessInfo: relnatts disagrees with indnatts for index %u",
+			 RelationGetRelid(relation));
 	amstrategies = aform->amstrategies;
 	amsupport = aform->amsupport;
 
@@ -1047,9 +1052,15 @@ RelationInitIndexAccessInfo(Relation relation)
 	 * Fill the strategy map and the support RegProcedure arrays.
 	 * (supportinfo is left as zeroes, and is filled on-the-fly when used)
 	 */
-	IndexSupportInitialize(iform,
+	IndexSupportInitialize(relation->rd_index,
 						   strategy, operator, support,
 						   amstrategies, amsupport, natts);
+
+	/*
+	 * expressions and predicate cache will be filled later
+	 */
+	relation->rd_indexprs = NIL;
+	relation->rd_indpred = NIL;
 }
 
 /*
@@ -1087,8 +1098,7 @@ IndexSupportInitialize(Form_pg_index iform,
 	{
 		OpClassCacheEnt *opcentry;
 
-		if (iform->indkey[attIndex] == InvalidAttrNumber ||
-			!OidIsValid(iform->indclass[attIndex]))
+		if (!OidIsValid(iform->indclass[attIndex]))
 			elog(ERROR, "IndexSupportInitialize: bogus pg_index tuple");
 
 		/* look up the info for this opclass, using a cache */
@@ -1729,8 +1739,8 @@ RelationClearRelation(Relation relation, bool rebuild)
 	 * with, we can only get rid of these fields:
 	 */
 	FreeTriggerDesc(relation->trigdesc);
-	if (relation->rd_index)
-		pfree(relation->rd_index);
+	if (relation->rd_indextuple)
+		pfree(relation->rd_indextuple);
 	if (relation->rd_am)
 		pfree(relation->rd_am);
 	if (relation->rd_rel)
@@ -2659,6 +2669,136 @@ insert_ordered_oid(List *list, Oid datum)
 	return list;
 }
 
+/*
+ * RelationGetIndexExpressions -- get the index expressions for an index
+ *
+ * We cache the result of transforming pg_index.indexprs into a node tree.
+ * If the rel is not an index or has no expressional columns, we return NIL.
+ * Otherwise, the returned tree is copied into the caller's memory context.
+ * (We don't want to return a pointer to the relcache copy, since it could
+ * disappear due to relcache invalidation.)
+ */
+List *
+RelationGetIndexExpressions(Relation relation)
+{
+	List	   *result;
+	Datum		exprsDatum;
+	bool		isnull;
+	char	   *exprsString;
+	MemoryContext oldcxt;
+
+	/* Quick exit if we already computed the result. */
+	if (relation->rd_indexprs)
+		return (List *) copyObject(relation->rd_indexprs);
+
+	/* Quick exit if there is nothing to do. */
+	if (relation->rd_indextuple == NULL ||
+		heap_attisnull(relation->rd_indextuple, Anum_pg_index_indexprs))
+		return NIL;
+
+	/*
+	 * We build the tree we intend to return in the caller's context.
+	 * After successfully completing the work, we copy it into the relcache
+	 * entry.  This avoids problems if we get some sort of
+	 * error partway through.
+	 *
+	 * We make use of the syscache's copy of pg_index's tupledesc
+	 * to access the non-fixed fields of the tuple.  We assume that
+	 * the syscache will be initialized before any access of a
+	 * partial index could occur.  (This would probably fail if we
+	 * were to allow partial indexes on system catalogs.)
+	 */
+	exprsDatum = SysCacheGetAttr(INDEXRELID, relation->rd_indextuple,
+								 Anum_pg_index_indexprs, &isnull);
+	Assert(!isnull);
+	exprsString = DatumGetCString(DirectFunctionCall1(textout, exprsDatum));
+	result = (List *) stringToNode(exprsString);
+	pfree(exprsString);
+
+	/*
+	 * Run the expressions through eval_const_expressions.  This is not just
+	 * an optimization, but is necessary, because the planner will be
+	 * comparing them to const-folded qual clauses, and may fail to detect
+	 * valid matches without this.
+	 */
+	result = (List *) eval_const_expressions((Node *) result);
+
+	/* May as well fix opfuncids too */
+	fix_opfuncids((Node *) result);
+
+	/* Now save a copy of the completed tree in the relcache entry. */
+	oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
+	relation->rd_indexprs = (List *) copyObject(result);
+	MemoryContextSwitchTo(oldcxt);
+
+	return result;
+}
+
+/*
+ * RelationGetIndexPredicate -- get the index predicate for an index
+ *
+ * We cache the result of transforming pg_index.indpred into a node tree.
+ * If the rel is not an index or has no predicate, we return NIL.
+ * Otherwise, the returned tree is copied into the caller's memory context.
+ * (We don't want to return a pointer to the relcache copy, since it could
+ * disappear due to relcache invalidation.)
+ */
+List *
+RelationGetIndexPredicate(Relation relation)
+{
+	List	   *result;
+	Datum		predDatum;
+	bool		isnull;
+	char	   *predString;
+	MemoryContext oldcxt;
+
+	/* Quick exit if we already computed the result. */
+	if (relation->rd_indpred)
+		return (List *) copyObject(relation->rd_indpred);
+
+	/* Quick exit if there is nothing to do. */
+	if (relation->rd_indextuple == NULL ||
+		heap_attisnull(relation->rd_indextuple, Anum_pg_index_indpred))
+		return NIL;
+
+	/*
+	 * We build the tree we intend to return in the caller's context.
+	 * After successfully completing the work, we copy it into the relcache
+	 * entry.  This avoids problems if we get some sort of
+	 * error partway through.
+	 *
+	 * We make use of the syscache's copy of pg_index's tupledesc
+	 * to access the non-fixed fields of the tuple.  We assume that
+	 * the syscache will be initialized before any access of a
+	 * partial index could occur.  (This would probably fail if we
+	 * were to allow partial indexes on system catalogs.)
+	 */
+	predDatum = SysCacheGetAttr(INDEXRELID, relation->rd_indextuple,
+								Anum_pg_index_indpred, &isnull);
+	Assert(!isnull);
+	predString = DatumGetCString(DirectFunctionCall1(textout, predDatum));
+	result = (List *) stringToNode(predString);
+	pfree(predString);
+
+	/*
+	 * Run the expression through eval_const_expressions.  This is not just
+	 * an optimization, but is necessary, because the planner will be
+	 * comparing it to const-folded qual clauses, and may fail to detect
+	 * valid matches without this.
+	 */
+	result = (List *) eval_const_expressions((Node *) result);
+
+	/* May as well fix opfuncids too */
+	fix_opfuncids((Node *) result);
+
+	/* Now save a copy of the completed tree in the relcache entry. */
+	oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
+	relation->rd_indpred = (List *) copyObject(result);
+	MemoryContextSwitchTo(oldcxt);
+
+	return result;
+}
+
 
 /*
  *	load_relcache_init_file, write_relcache_init_file
@@ -2829,14 +2969,19 @@ load_relcache_init_file(void)
 			if (rel->rd_isnailed)
 				nailed_indexes++;
 
-			/* next, read the pg_index tuple form */
+			/* next, read the pg_index tuple */
 			if ((nread = fread(&len, 1, sizeof(len), fp)) != sizeof(len))
 				goto read_failed;
 
-			rel->rd_index = (Form_pg_index) palloc(len);
-			if ((nread = fread(rel->rd_index, 1, len, fp)) != len)
+			rel->rd_indextuple = (HeapTuple) palloc(len);
+			if ((nread = fread(rel->rd_indextuple, 1, len, fp)) != len)
 				goto read_failed;
 
+			/* Fix up internal pointers in the tuple -- see heap_copytuple */
+			rel->rd_indextuple->t_datamcxt = CurrentMemoryContext;
+			rel->rd_indextuple->t_data = (HeapTupleHeader) ((char *) rel->rd_indextuple + HEAPTUPLESIZE);
+			rel->rd_index = (Form_pg_index) GETSTRUCT(rel->rd_indextuple);
+
 			/* next, read the access method tuple form */
 			if ((nread = fread(&len, 1, sizeof(len), fp)) != sizeof(len))
 				goto read_failed;
@@ -2904,6 +3049,7 @@ load_relcache_init_file(void)
 				nailed_rels++;
 
 			Assert(rel->rd_index == NULL);
+			Assert(rel->rd_indextuple == NULL);
 			Assert(rel->rd_am == NULL);
 			Assert(rel->rd_indexcxt == NULL);
 			Assert(rel->rd_istrat == NULL);
@@ -2917,11 +3063,13 @@ load_relcache_init_file(void)
 		 * format is complex and subject to change).  They must be rebuilt
 		 * if needed by RelationCacheInitializePhase2.	This is not
 		 * expected to be a big performance hit since few system catalogs
-		 * have such.
+		 * have such.  Ditto for index expressions and predicates.
 		 */
 		rel->rd_rules = NULL;
 		rel->rd_rulescxt = NULL;
 		rel->trigdesc = NULL;
+		rel->rd_indexprs = NIL;
+		rel->rd_indpred = NIL;
 
 		/*
 		 * Reset transient-state fields in the relcache entry
@@ -3076,26 +3224,15 @@ write_relcache_init_file(void)
 		if (rel->rd_rel->relkind == RELKIND_INDEX)
 		{
 			Form_pg_am	am = rel->rd_am;
-			HeapTuple	tuple;
 
-			/*
-			 * We need to write the index tuple form, but this is a bit
-			 * tricky since it's a variable-length struct.  Rather than
-			 * hoping to intuit the length, fetch the pg_index tuple
-			 * afresh using the syscache, and write that.
-			 */
-			tuple = SearchSysCache(INDEXRELID,
-								 ObjectIdGetDatum(RelationGetRelid(rel)),
-								   0, 0, 0);
-			if (!HeapTupleIsValid(tuple))
-				elog(ERROR, "write_relcache_init_file: no pg_index entry for index %u",
-					 RelationGetRelid(rel));
-			len = tuple->t_len - tuple->t_data->t_hoff;
+			/* write the pg_index tuple */
+			/* we assume this was created by heap_copytuple! */
+			len = HEAPTUPLESIZE + rel->rd_indextuple->t_len;
 			if (fwrite(&len, 1, sizeof(len), fp) != sizeof(len))
-				elog(FATAL, "cannot write init file -- index tuple form length");
-			if (fwrite(GETSTRUCT(tuple), 1, len, fp) != len)
-				elog(FATAL, "cannot write init file -- index tuple form");
-			ReleaseSysCache(tuple);
+				elog(FATAL, "cannot write init file -- index tuple length");
+
+			if (fwrite(rel->rd_indextuple, 1, len, fp) != len)
+				elog(FATAL, "cannot write init file -- index tuple");
 
 			/* next, write the access method tuple form */
 			len = sizeof(FormData_pg_am);
diff --git a/src/bin/psql/describe.c b/src/bin/psql/describe.c
index 4aeac0c44e6..a20cc1a4207 100644
--- a/src/bin/psql/describe.c
+++ b/src/bin/psql/describe.c
@@ -3,7 +3,7 @@
  *
  * Copyright 2000-2002 by PostgreSQL Global Development Group
  *
- * $Header: /cvsroot/pgsql/src/bin/psql/describe.c,v 1.76 2003/03/27 16:57:39 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/bin/psql/describe.c,v 1.77 2003/05/28 16:03:59 tgl Exp $
  */
 #include "postgres_fe.h"
 #include "describe.h"
@@ -711,10 +711,7 @@ describeOneTableDetails(const char *schemaname,
 	headers[cols] = NULL;
 
 	/* Get column info (index requires additional checks) */
-	if (tableinfo.relkind == 'i')
-		printfPQExpBuffer(&buf, "SELECT\n  CASE i.indproc WHEN ('-'::pg_catalog.regproc) THEN a.attname\n  ELSE SUBSTR(pg_catalog.pg_get_indexdef(attrelid),\n  POSITION('(' in pg_catalog.pg_get_indexdef(attrelid)))\n  END,");
-	else
-		printfPQExpBuffer(&buf, "SELECT a.attname,");
+	printfPQExpBuffer(&buf, "SELECT a.attname,");
 	appendPQExpBuffer(&buf, "\n  pg_catalog.format_type(a.atttypid, a.atttypmod),"
 					  "\n  (SELECT substring(d.adsrc for 128) FROM pg_catalog.pg_attrdef d"
 					  "\n   WHERE d.adrelid = a.attrelid AND d.adnum = a.attnum AND a.atthasdef),"
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index 2c28ffcabc5..443af8e8d6a 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -37,7 +37,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: catversion.h,v 1.196 2003/05/26 00:11:27 tgl Exp $
+ * $Id: catversion.h,v 1.197 2003/05/28 16:03:59 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	200305241
+#define CATALOG_VERSION_NO	200305271
 
 #endif
diff --git a/src/include/catalog/dependency.h b/src/include/catalog/dependency.h
index 7a17ce92873..512c17a43cf 100644
--- a/src/include/catalog/dependency.h
+++ b/src/include/catalog/dependency.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: dependency.h,v 1.7 2003/03/06 22:54:49 tgl Exp $
+ * $Id: dependency.h,v 1.8 2003/05/28 16:03:59 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -91,6 +91,11 @@ extern void recordDependencyOnExpr(const ObjectAddress *depender,
 					   Node *expr, List *rtable,
 					   DependencyType behavior);
 
+extern void recordDependencyOnSingleRelExpr(const ObjectAddress *depender,
+					   Node *expr, Oid relId,
+					   DependencyType behavior,
+					   DependencyType self_behavior);
+
 /* in pg_depend.c */
 
 extern void recordDependencyOn(const ObjectAddress *depender,
diff --git a/src/include/catalog/index.h b/src/include/catalog/index.h
index eb4e5f8814b..5833a92e2e2 100644
--- a/src/include/catalog/index.h
+++ b/src/include/catalog/index.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: index.h,v 1.50 2002/09/23 00:42:48 tgl Exp $
+ * $Id: index.h,v 1.51 2003/05/28 16:04:00 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -18,6 +18,7 @@
 #include "catalog/pg_index.h"
 #include "nodes/execnodes.h"
 
+
 #define DEFAULT_INDEX_TYPE	"btree"
 
 /* Typedef for callback function for IndexBuildHeapScan */
@@ -40,12 +41,12 @@ extern Oid index_create(Oid heapRelationId,
 
 extern void index_drop(Oid indexId);
 
-extern IndexInfo *BuildIndexInfo(Form_pg_index indexStruct);
+extern IndexInfo *BuildIndexInfo(Relation index);
 
 extern void FormIndexDatum(IndexInfo *indexInfo,
 			   HeapTuple heapTuple,
 			   TupleDesc heapDescriptor,
-			   MemoryContext resultCxt,
+			   EState *estate,
 			   Datum *datum,
 			   char *nullv);
 
diff --git a/src/include/catalog/pg_index.h b/src/include/catalog/pg_index.h
index ecdce77f17d..2984b862aa5 100644
--- a/src/include/catalog/pg_index.h
+++ b/src/include/catalog/pg_index.h
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: pg_index.h,v 1.30 2003/03/10 22:28:19 tgl Exp $
+ * $Id: pg_index.h,v 1.31 2003/05/28 16:04:00 tgl Exp $
  *
  * NOTES
  *	  the genbki.sh script reads this file and generates .bki
@@ -35,18 +35,19 @@ CATALOG(pg_index) BKI_WITHOUT_OIDS
 {
 	Oid			indexrelid;		/* OID of the index */
 	Oid			indrelid;		/* OID of the relation it indexes */
-	regproc		indproc;		/* OID of function for functional index */
-	int2vector	indkey;			/* column numbers of indexed attributes */
+	int2vector	indkey;			/* column numbers of indexed cols, or 0 */
 	oidvector	indclass;		/* opclass identifiers */
-	bool		indisclustered; /* is this the index last clustered by? */
+	int2		indnatts;		/* number of columns in index */
 	bool		indisunique;	/* is this a unique index? */
 	bool		indisprimary;	/* is this index for primary key? */
-	Oid			indreference;	/* oid of index of referenced relation (ie
-								 * - this index for foreign key) */
+	bool		indisclustered; /* is this the index last clustered by? */
 
-	/* VARIABLE LENGTH FIELD: */
+	/* VARIABLE LENGTH FIELDS: */
+	text		indexprs;		/* expression trees for index attributes
+								 * that are not simple column references;
+								 * one for each zero entry in indkey[] */
 	text		indpred;		/* expression tree for predicate, if a
-								 * partial index */
+								 * partial index; else NULL */
 } FormData_pg_index;
 
 /* ----------------
@@ -63,13 +64,13 @@ typedef FormData_pg_index *Form_pg_index;
 #define Natts_pg_index					10
 #define Anum_pg_index_indexrelid		1
 #define Anum_pg_index_indrelid			2
-#define Anum_pg_index_indproc			3
-#define Anum_pg_index_indkey			4
-#define Anum_pg_index_indclass			5
-#define Anum_pg_index_indisclustered	6
-#define Anum_pg_index_indisunique		7
-#define Anum_pg_index_indisprimary		8
-#define Anum_pg_index_indreference		9
+#define Anum_pg_index_indkey			3
+#define Anum_pg_index_indclass			4
+#define Anum_pg_index_indnatts			5
+#define Anum_pg_index_indisunique		6
+#define Anum_pg_index_indisprimary		7
+#define Anum_pg_index_indisclustered	8
+#define Anum_pg_index_indexprs			9
 #define Anum_pg_index_indpred			10
 
 #endif   /* PG_INDEX_H */
diff --git a/src/include/catalog/pg_opclass.h b/src/include/catalog/pg_opclass.h
index 809cde3da02..f9de8fa28c8 100644
--- a/src/include/catalog/pg_opclass.h
+++ b/src/include/catalog/pg_opclass.h
@@ -8,7 +8,7 @@
  * <opcamid, opcname> --- that is, there is a row for each valid combination
  * of opclass name and index access method type.  This row specifies the
  * expected input data type for the opclass (the type of the heap column,
- * or the function output type in the case of a functional index).	Note
+ * or the expression output type in the case of an index expression).  Note
  * that types binary-coercible to the specified type will be accepted too.
  *
  * For a given <opcamid, opcintype> pair, there can be at most one row that
@@ -26,7 +26,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: pg_opclass.h,v 1.49 2003/05/26 00:11:27 tgl Exp $
+ * $Id: pg_opclass.h,v 1.50 2003/05/28 16:04:00 tgl Exp $
  *
  * NOTES
  *	  the genbki.sh script reads this file and generates .bki
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index 17e27969f53..68a3bb9b1cd 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: execnodes.h,v 1.97 2003/04/08 23:20:04 tgl Exp $
+ * $Id: execnodes.h,v 1.98 2003/05/28 16:04:00 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -27,19 +27,17 @@
 /* ----------------
  *	  IndexInfo information
  *
- *		this class holds the information needed to construct new index
+ *		this struct holds the information needed to construct new index
  *		entries for a particular index.  Used for both index_build and
  *		retail creation of index entries.
  *
  *		NumIndexAttrs		number of columns in this index
- *							(1 if a func. index, else same as NumKeyAttrs)
- *		NumKeyAttrs			number of key attributes for this index
- *							(ie, number of attrs from underlying relation)
  *		KeyAttrNumbers		underlying-rel attribute numbers used as keys
+ *							(zeroes indicate expressions)
+ *		Expressions			expr trees for expression entries, or NIL if none
+ *		ExpressionsState	exec state for expressions, or NIL if none
  *		Predicate			partial-index predicate, or NIL if none
  *		PredicateState		exec state for predicate, or NIL if none
- *		FuncOid				OID of function, or InvalidOid if not f. index
- *		FuncInfo			fmgr lookup data for function, if FuncOid valid
  *		Unique				is it a unique index?
  * ----------------
  */
@@ -47,12 +45,11 @@ typedef struct IndexInfo
 {
 	NodeTag		type;
 	int			ii_NumIndexAttrs;
-	int			ii_NumKeyAttrs;
 	AttrNumber	ii_KeyAttrNumbers[INDEX_MAX_KEYS];
+	List	   *ii_Expressions;	/* list of Expr */
+	List	   *ii_ExpressionsState; /* list of ExprState */
 	List	   *ii_Predicate;	/* list of Expr */
 	List	   *ii_PredicateState; /* list of ExprState */
-	Oid			ii_FuncOid;
-	FmgrInfo	ii_FuncInfo;
 	bool		ii_Unique;
 } IndexInfo;
 
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index 4ad35b683a7..25d719dd8fc 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: parsenodes.h,v 1.237 2003/05/02 20:54:36 tgl Exp $
+ * $Id: parsenodes.h,v 1.238 2003/05/28 16:04:02 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -353,17 +353,15 @@ typedef struct ColumnDef
 /*
  * IndexElem - index parameters (used in CREATE INDEX)
  *
- * For a plain index, each 'name' is an attribute name in the heap relation;
- * 'funcname' and 'args' are NIL.  For a functional index, only one IndexElem
- * is allowed.	It has name = NULL, funcname = name of function and args =
- * list of attribute names that are the function's arguments.
+ * For a plain index attribute, 'name' is the name of the table column to
+ * index, and 'expr' is NULL.  For an index expression, 'name' is NULL and
+ * 'expr' is the expression tree.
  */
 typedef struct IndexElem
 {
 	NodeTag		type;
 	char	   *name;			/* name of attribute to index, or NULL */
-	List	   *funcname;		/* qualified name of function */
-	List	   *args;			/* list of names of function arguments */
+	Node	   *expr;			/* expression to index, or NULL */
 	List	   *opclass;		/* name of desired opclass; NIL = default */
 } IndexElem;
 
@@ -1271,8 +1269,8 @@ typedef struct IndexStmt
 	char	   *accessMethod;	/* name of access method (eg. btree) */
 	List	   *indexParams;	/* a list of IndexElem */
 	Node	   *whereClause;	/* qualification (partial-index predicate) */
-	List	   *rangetable;		/* range table for qual, filled in by
-								 * transformStmt() */
+	List	   *rangetable;		/* range table for qual and/or expressions,
+								 * filled in by transformStmt() */
 	bool		unique;			/* is index unique? */
 	bool		primary;		/* is index on primary key? */
 	bool		isconstraint;	/* is it from a CONSTRAINT clause? */
diff --git a/src/include/nodes/relation.h b/src/include/nodes/relation.h
index 03240d64153..4f770b7ca10 100644
--- a/src/include/nodes/relation.h
+++ b/src/include/nodes/relation.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: relation.h,v 1.79 2003/02/08 20:20:55 tgl Exp $
+ * $Id: relation.h,v 1.80 2003/05/28 16:04:02 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -227,15 +227,16 @@ typedef struct RelOptInfo
  *		and indexes, but that created confusion without actually doing anything
  *		useful.  So now we have a separate IndexOptInfo struct for indexes.
  *
- *		ncolumns and nkeys are the same except for a functional index,
- *		wherein ncolumns is 1 (the single function output) while nkeys
- *		is the number of table columns passed to the function. classlist[]
- *		and ordering[] have ncolumns entries, while indexkeys[] has nkeys
- *		entries.
+ *		classlist[], indexkeys[], and ordering[] have ncolumns entries.
+ *		Zeroes in the indexkeys[] array indicate index columns that are
+ *		expressions; there is one element in indexprs for each such column.
  *
- *		Note: for historical reasons, the arrays classlist, indexkeys and
- *		ordering have an extra entry that is always zero.  Some code scans
- *		until it sees a zero rather than looking at ncolumns or nkeys.
+ *		Note: for historical reasons, the classlist and ordering arrays have
+ *		an extra entry that is always zero.  Some code scans until it sees a
+ *		zero entry, rather than looking at ncolumns.
+ *
+ *		The indexprs and indpred expressions have been run through
+ *		eval_const_expressions() for ease of matching to WHERE clauses.
  */
 
 typedef struct IndexOptInfo
@@ -250,15 +251,14 @@ typedef struct IndexOptInfo
 
 	/* index descriptor information */
 	int			ncolumns;		/* number of columns in index */
-	int			nkeys;			/* number of keys used by index */
 	Oid		   *classlist;		/* OIDs of operator classes for columns */
-	int		   *indexkeys;		/* column numbers of index's keys */
+	int		   *indexkeys;		/* column numbers of index's keys, or 0 */
 	Oid		   *ordering;		/* OIDs of sort operators for each column */
 	Oid			relam;			/* OID of the access method (in pg_am) */
 
 	RegProcedure amcostestimate;	/* OID of the access method's cost fcn */
 
-	Oid			indproc;		/* OID of func if functional index, else 0 */
+	List	   *indexprs;		/* expressions for non-simple index columns */
 	List	   *indpred;		/* predicate if a partial index, else NIL */
 	bool		unique;			/* true if a unique index */
 
@@ -289,9 +289,8 @@ typedef struct PathKeyItem
 
 	/*
 	 * key typically points to a Var node, ie a relation attribute, but it
-	 * can also point to a FuncExpr clause representing the value indexed by a
-	 * functional index.  Someday we might allow arbitrary expressions as
-	 * path keys, so don't assume more than you must.
+	 * can also point to an arbitrary expression representing the value
+	 * indexed by an index expression.
 	 */
 } PathKeyItem;
 
diff --git a/src/include/optimizer/clauses.h b/src/include/optimizer/clauses.h
index 5a38d6ef2ad..77dd3765951 100644
--- a/src/include/optimizer/clauses.h
+++ b/src/include/optimizer/clauses.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: clauses.h,v 1.62 2003/02/04 00:50:01 tgl Exp $
+ * $Id: clauses.h,v 1.63 2003/05/28 16:04:02 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -28,9 +28,6 @@ extern Expr *make_opclause(Oid opno, Oid opresulttype, bool opretset,
 extern Node *get_leftop(Expr *clause);
 extern Node *get_rightop(Expr *clause);
 
-extern Expr *make_funcclause(Oid funcid, Oid funcresulttype, bool funcretset,
-							 CoercionForm funcformat, List *funcargs);
-
 extern bool not_clause(Node *clause);
 extern Expr *make_notclause(Expr *notclause);
 extern Expr *get_notclausearg(Expr *notclause);
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index a9ff7325c1e..fd5e0c56b76 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: rel.h,v 1.64 2002/11/23 03:59:09 momjian Exp $
+ * $Id: rel.h,v 1.65 2003/05/28 16:04:02 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -132,6 +132,8 @@ typedef struct RelationData
 
 	/* These are non-NULL only for an index relation: */
 	Form_pg_index rd_index;		/* pg_index tuple describing this index */
+	struct HeapTupleData *rd_indextuple; /* all of pg_index tuple */
+	/* "struct HeapTupleData *" avoids need to include htup.h here  */
 	Form_pg_am	rd_am;			/* pg_am tuple for index's AM */
 
 	/* index access support info (used only for an index relation) */
@@ -142,6 +144,8 @@ typedef struct RelationData
 	struct FmgrInfo *rd_supportinfo;	/* lookup info for support
 										 * procedures */
 	/* "struct FmgrInfo" avoids need to include fmgr.h here */
+	List	   *rd_indexprs;	/* index expression trees, if any */
+	List	   *rd_indpred;		/* index predicate tree, if any */
 
 	/* statistics collection area */
 	PgStat_Info pgstat_info;
diff --git a/src/include/utils/relcache.h b/src/include/utils/relcache.h
index c0495284912..f28d23a6268 100644
--- a/src/include/utils/relcache.h
+++ b/src/include/utils/relcache.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: relcache.h,v 1.34 2002/08/06 02:36:35 tgl Exp $
+ * $Id: relcache.h,v 1.35 2003/05/28 16:04:02 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -32,6 +32,8 @@ extern void RelationClose(Relation relation);
  * Routines to compute/retrieve additional cached information
  */
 extern List *RelationGetIndexList(Relation relation);
+extern List *RelationGetIndexExpressions(Relation relation);
+extern List *RelationGetIndexPredicate(Relation relation);
 
 extern void RelationInitIndexAccessInfo(Relation relation);
 
diff --git a/src/interfaces/python/tutorial/syscat.py b/src/interfaces/python/tutorial/syscat.py
index 1ab1d5840c2..46d6d46ae07 100755
--- a/src/interfaces/python/tutorial/syscat.py
+++ b/src/interfaces/python/tutorial/syscat.py
@@ -36,8 +36,8 @@ def list_simple_ind(pgcnx):
 			ic.relname AS index_name, a.attname
 		FROM pg_class bc, pg_class ic, pg_index i, pg_attribute a
 		WHERE i.indrelid = bc.oid AND i.indexrelid = bc.oid
-				AND i.indkey[0] = a.attnum AND a.attrelid = bc.oid
-				AND i.indproc = '0'::oid AND a.attisdropped = 'f'
+				AND i.indkey[0] = a.attnum AND i.indnatts = 1
+				AND a.attrelid = bc.oid AND a.attisdropped = 'f'
 		ORDER BY class_name, index_name, attname""")
 	return result
 
diff --git a/src/test/regress/expected/create_index.out b/src/test/regress/expected/create_index.out
index 243198d79f2..d82ed8c4e89 100644
--- a/src/test/regress/expected/create_index.out
+++ b/src/test/regress/expected/create_index.out
@@ -81,3 +81,17 @@ INSERT INTO func_index_heap VALUES('ABCD', 'EF');
 ERROR:  Cannot insert a duplicate key into unique index func_index_index
 -- but this shouldn't:
 INSERT INTO func_index_heap VALUES('QWERTY');
+--
+-- Same test, expressional index
+--
+DROP TABLE func_index_heap;
+CREATE TABLE func_index_heap (f1 text, f2 text);
+CREATE UNIQUE INDEX func_index_index on func_index_heap ((f1 || f2) text_ops);
+INSERT INTO func_index_heap VALUES('ABC','DEF');
+INSERT INTO func_index_heap VALUES('AB','CDEFG');
+INSERT INTO func_index_heap VALUES('QWE','RTY');
+-- this should fail because of unique index:
+INSERT INTO func_index_heap VALUES('ABCD', 'EF');
+ERROR:  Cannot insert a duplicate key into unique index func_index_index
+-- but this shouldn't:
+INSERT INTO func_index_heap VALUES('QWERTY');
diff --git a/src/test/regress/expected/sanity_check.out b/src/test/regress/expected/sanity_check.out
index 2dd74613d99..87e1943e5a2 100644
--- a/src/test/regress/expected/sanity_check.out
+++ b/src/test/regress/expected/sanity_check.out
@@ -75,7 +75,7 @@ FROM pg_class c LEFT JOIN pg_namespace n ON n.oid = relnamespace
 WHERE relhasoids
     AND ((nspname ~ '^pg_') IS NOT FALSE)
     AND NOT EXISTS (SELECT 1 FROM pg_index i WHERE indrelid = c.oid
-                    AND indkey[0] = -2 AND indkey[1] = 0 AND indisunique);
+                    AND indkey[0] = -2 AND indnatts = 1 AND indisunique);
  relname | nspname 
 ---------+---------
 (0 rows)
diff --git a/src/test/regress/sql/create_index.sql b/src/test/regress/sql/create_index.sql
index fe49d4ec2e2..383a7a1a9f9 100644
--- a/src/test/regress/sql/create_index.sql
+++ b/src/test/regress/sql/create_index.sql
@@ -104,3 +104,19 @@ INSERT INTO func_index_heap VALUES('QWE','RTY');
 INSERT INTO func_index_heap VALUES('ABCD', 'EF');
 -- but this shouldn't:
 INSERT INTO func_index_heap VALUES('QWERTY');
+
+
+--
+-- Same test, expressional index
+--
+DROP TABLE func_index_heap;
+CREATE TABLE func_index_heap (f1 text, f2 text);
+CREATE UNIQUE INDEX func_index_index on func_index_heap ((f1 || f2) text_ops);
+
+INSERT INTO func_index_heap VALUES('ABC','DEF');
+INSERT INTO func_index_heap VALUES('AB','CDEFG');
+INSERT INTO func_index_heap VALUES('QWE','RTY');
+-- this should fail because of unique index:
+INSERT INTO func_index_heap VALUES('ABCD', 'EF');
+-- but this shouldn't:
+INSERT INTO func_index_heap VALUES('QWERTY');
diff --git a/src/test/regress/sql/sanity_check.sql b/src/test/regress/sql/sanity_check.sql
index 50b1a2659b2..108d4f78124 100644
--- a/src/test/regress/sql/sanity_check.sql
+++ b/src/test/regress/sql/sanity_check.sql
@@ -21,4 +21,4 @@ FROM pg_class c LEFT JOIN pg_namespace n ON n.oid = relnamespace
 WHERE relhasoids
     AND ((nspname ~ '^pg_') IS NOT FALSE)
     AND NOT EXISTS (SELECT 1 FROM pg_index i WHERE indrelid = c.oid
-                    AND indkey[0] = -2 AND indkey[1] = 0 AND indisunique);
+                    AND indkey[0] = -2 AND indnatts = 1 AND indisunique);
diff --git a/src/tutorial/syscat.source b/src/tutorial/syscat.source
index 4ef6d513bf4..ab5e26c94b5 100644
--- a/src/tutorial/syscat.source
+++ b/src/tutorial/syscat.source
@@ -7,7 +7,7 @@
 -- Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
 -- Portions Copyright (c) 1994, Regents of the University of California
 --
--- $Id: syscat.source,v 1.7 2002/06/20 20:29:54 momjian Exp $
+-- $Id: syscat.source,v 1.8 2003/05/28 16:04:02 tgl Exp $
 --
 ---------------------------------------------------------------------------
 
@@ -31,8 +31,8 @@ SELECT relname
 
 
 --
--- lists all simple indices (ie. those that are not defined over a function
--- of several attributes)
+-- lists all simple indices (ie. those that are defined over one simple
+-- column reference)
 --
 SELECT bc.relname AS class_name, 
        ic.relname AS index_name, 
@@ -44,8 +44,8 @@ SELECT bc.relname AS class_name,
   WHERE i.indrelid = bc.oid
      and i.indexrelid = ic.oid
      and i.indkey[0] = a.attnum
+     and i.indnatts = 1
      and a.attrelid = bc.oid
-     and i.indproc = '0'::oid   -- no functional indices
   ORDER BY class_name, index_name, attname;