static List *init_execution_state(List *queryTree_list,
SQLFunctionCachePtr fcache,
bool lazyEvalOK);
-static void init_sql_fcache(FmgrInfo *finfo, Oid collation, bool lazyEvalOK);
+static void init_sql_fcache(FunctionCallInfo fcinfo, Oid collation, bool lazyEvalOK);
static void postquel_start(execution_state *es, SQLFunctionCachePtr fcache);
static bool postquel_getnext(execution_state *es, SQLFunctionCachePtr fcache);
static void postquel_end(execution_state *es);
MemoryContext resultcontext);
static void sql_exec_error_callback(void *arg);
static void ShutdownSQLFunction(Datum arg);
+static bool coerce_fn_result_column(TargetEntry *src_tle,
+ Oid res_type, int32 res_typmod,
+ bool tlist_is_modifiable,
+ List **upper_tlist,
+ bool *upper_tlist_nontrivial);
static void sqlfunction_startup(DestReceiver *self, int operation, TupleDesc typeinfo);
static bool sqlfunction_receive(TupleTableSlot *slot, DestReceiver *self);
static void sqlfunction_shutdown(DestReceiver *self);
* Initialize the SQLFunctionCache for a SQL function
*/
static void
-init_sql_fcache(FmgrInfo *finfo, Oid collation, bool lazyEvalOK)
+init_sql_fcache(FunctionCallInfo fcinfo, Oid collation, bool lazyEvalOK)
{
+ FmgrInfo *finfo = fcinfo->flinfo;
Oid foid = finfo->fn_oid;
MemoryContext fcontext;
MemoryContext oldcontext;
Oid rettype;
+ TupleDesc rettupdesc;
HeapTuple procedureTuple;
Form_pg_proc procedureStruct;
SQLFunctionCachePtr fcache;
List *raw_parsetree_list;
List *queryTree_list;
List *flat_query_list;
+ List *resulttlist;
ListCell *lc;
Datum tmp;
bool isNull;
MemoryContextSetIdentifier(fcontext, fcache->fname);
/*
- * get the result type from the procedure tuple, and check for polymorphic
- * result type; if so, find out the actual result type.
+ * Resolve any polymorphism, obtaining the actual result type, and the
+ * corresponding tupdesc if it's a rowtype.
*/
- rettype = procedureStruct->prorettype;
-
- if (IsPolymorphicType(rettype))
- {
- rettype = get_fn_expr_rettype(finfo);
- if (rettype == InvalidOid) /* this probably should not happen */
- ereport(ERROR,
- (errcode(ERRCODE_DATATYPE_MISMATCH),
- errmsg("could not determine actual result type for function declared to return type %s",
- format_type_be(procedureStruct->prorettype))));
- }
+ (void) get_call_result_type(fcinfo, &rettype, &rettupdesc);
fcache->rettype = rettype;
* Check that the function returns the type it claims to. Although in
* simple cases this was already done when the function was defined, we
* have to recheck because database objects used in the function's queries
- * might have changed type. We'd have to do it anyway if the function had
- * any polymorphic arguments.
+ * might have changed type. We'd have to recheck anyway if the function
+ * had any polymorphic arguments. Moreover, check_sql_fn_retval takes
+ * care of injecting any required column type coercions. (But we don't
+ * ask it to insert nulls for dropped columns; the junkfilter handles
+ * that.)
*
* Note: we set fcache->returnsTuple according to whether we are returning
* the whole tuple result or just a single column. In the latter case we
* lazy eval mode in that case; otherwise we'd need extra code to expand
* the rowtype column into multiple columns, since we have no way to
* notify the caller that it should do that.)
- *
- * check_sql_fn_retval will also construct a JunkFilter we can use to
- * coerce the returned rowtype to the desired form (unless the result type
- * is VOID, in which case there's nothing to coerce to).
*/
- fcache->returnsTuple = check_sql_fn_retval(foid,
+ fcache->returnsTuple = check_sql_fn_retval(flat_query_list,
rettype,
- flat_query_list,
- NULL,
- &fcache->junkFilter);
+ rettupdesc,
+ false,
+ &resulttlist);
+
+ /*
+ * Construct a JunkFilter we can use to coerce the returned rowtype to the
+ * desired form, unless the result type is VOID, in which case there's
+ * nothing to coerce to. (XXX Frequently, the JunkFilter isn't doing
+ * anything very interesting, but much of this module expects it to be
+ * there anyway.)
+ */
+ if (rettype != VOIDOID)
+ {
+ TupleTableSlot *slot = MakeSingleTupleTableSlot(NULL,
+ &TTSOpsMinimalTuple);
+
+ /*
+ * If the result is composite, *and* we are returning the whole tuple
+ * result, we need to insert nulls for any dropped columns. In the
+ * single-column-result case, there might be dropped columns within
+ * the composite column value, but it's not our problem here. There
+ * should be no resjunk entries in resulttlist, so in the second case
+ * the JunkFilter is certainly a no-op.
+ */
+ if (rettupdesc && fcache->returnsTuple)
+ fcache->junkFilter = ExecInitJunkFilterConversion(resulttlist,
+ rettupdesc,
+ slot);
+ else
+ fcache->junkFilter = ExecInitJunkFilter(resulttlist, slot);
+ }
if (fcache->returnsTuple)
{
if (fcache == NULL)
{
- init_sql_fcache(fcinfo->flinfo, PG_GET_COLLATION(), lazyEvalOK);
+ init_sql_fcache(fcinfo, PG_GET_COLLATION(), lazyEvalOK);
fcache = (SQLFunctionCachePtr) fcinfo->flinfo->fn_extra;
}
* check_sql_fn_retval() -- check return value of a list of sql parse trees.
*
* The return value of a sql function is the value returned by the last
- * canSetTag query in the function. We do some ad-hoc type checking here
- * to be sure that the user is returning the type he claims. There are
- * also a couple of strange-looking features to assist callers in dealing
- * with allowed special cases, such as binary-compatible result types.
- *
- * For a polymorphic function the passed rettype must be the actual resolved
- * output type of the function; we should never see a polymorphic pseudotype
- * such as ANYELEMENT as rettype. (This means we can't check the type during
- * function definition of a polymorphic function.)
+ * canSetTag query in the function. We do some ad-hoc type checking and
+ * coercion here to ensure that the function returns what it's supposed to.
+ * Note that we may actually modify the last query to make it match!
*
* This function returns true if the sql function returns the entire tuple
* result of its final statement, or false if it returns just the first column
* Note that because we allow "SELECT rowtype_expression", the result can be
* false even when the declared function return type is a rowtype.
*
- * If modifyTargetList isn't NULL, the function will modify the final
- * statement's targetlist in two cases:
- * (1) if the tlist returns values that are binary-coercible to the expected
- * type rather than being exactly the expected type. RelabelType nodes will
- * be inserted to make the result types match exactly.
- * (2) if there are dropped columns in the declared result rowtype. NULL
- * output columns will be inserted in the tlist to match them.
- * (Obviously the caller must pass a parsetree that is okay to modify when
- * using this flag.) Note that this flag does not affect whether the tlist is
- * considered to be a legal match to the result type, only how we react to
- * allowed not-exact-match cases. *modifyTargetList will be set true iff
- * we had to make any "dangerous" changes that could modify the semantics of
- * the statement. If it is set true, the caller should not use the modified
- * statement, but for simplicity we apply the changes anyway.
+ * For a polymorphic function the passed rettype must be the actual resolved
+ * output type of the function; we should never see a polymorphic pseudotype
+ * such as ANYELEMENT as rettype. (This means we can't check the type during
+ * function definition of a polymorphic function.) If the function returns
+ * composite, the passed rettupdesc should describe the expected output.
+ * If rettupdesc is NULL, we can't verify that the output matches; that
+ * should only happen in fmgr_sql_validator(), or when the function returns
+ * RECORD and the caller doesn't actually care which composite type it is.
+ * (Typically, rettype and rettupdesc are computed by get_call_result_type
+ * or a sibling function.)
+ *
+ * In addition to coercing individual output columns, we can modify the
+ * output to include dummy NULL columns for any dropped columns appearing
+ * in rettupdesc. This is done only if the caller asks for it.
*
- * If junkFilter isn't NULL, then *junkFilter is set to a JunkFilter defined
- * to convert the function's tuple result to the correct output tuple type.
- * Exception: if the function is defined to return VOID then *junkFilter is
- * set to NULL.
+ * If resultTargetList isn't NULL, then *resultTargetList is set to the
+ * targetlist that defines the final statement's result. Exception: if the
+ * function is defined to return VOID then *resultTargetList is set to NIL.
*/
bool
-check_sql_fn_retval(Oid func_id, Oid rettype, List *queryTreeList,
- bool *modifyTargetList,
- JunkFilter **junkFilter)
+check_sql_fn_retval(List *queryTreeList,
+ Oid rettype, TupleDesc rettupdesc,
+ bool insertDroppedCols,
+ List **resultTargetList)
{
+ bool is_tuple_result = false;
Query *parse;
- List **tlist_ptr;
+ ListCell *parse_cell;
List *tlist;
int tlistlen;
+ bool tlist_is_modifiable;
char fn_typtype;
- Oid restype;
+ List *upper_tlist = NIL;
+ bool upper_tlist_nontrivial = false;
ListCell *lc;
+ /* Caller must have resolved any polymorphism */
AssertArg(!IsPolymorphicType(rettype));
- if (modifyTargetList)
- *modifyTargetList = false; /* initialize for no change */
- if (junkFilter)
- *junkFilter = NULL; /* initialize in case of VOID result */
+ if (resultTargetList)
+ *resultTargetList = NIL; /* initialize in case of VOID result */
/*
* If it's declared to return VOID, we don't care what's in the function.
* the user wrote.
*/
parse = NULL;
+ parse_cell = NULL;
foreach(lc, queryTreeList)
{
Query *q = lfirst_node(Query, lc);
if (q->canSetTag)
+ {
parse = q;
+ parse_cell = lc;
+ }
}
/*
if (parse &&
parse->commandType == CMD_SELECT)
{
- tlist_ptr = &parse->targetList;
tlist = parse->targetList;
+ /* tlist is modifiable unless it's a dummy in a setop query */
+ tlist_is_modifiable = (parse->setOperations == NULL);
}
else if (parse &&
(parse->commandType == CMD_INSERT ||
parse->commandType == CMD_DELETE) &&
parse->returningList)
{
- tlist_ptr = &parse->returningList;
tlist = parse->returningList;
+ /* returningList can always be modified */
+ tlist_is_modifiable = true;
}
else
{
/*
* OK, check that the targetlist returns something matching the declared
- * type.
+ * type, and modify it if necessary. If possible, we insert any coercion
+ * steps right into the final statement's targetlist. However, that might
+ * risk changes in the statement's semantics --- we can't safely change
+ * the output type of a grouping column, for instance. In such cases we
+ * handle coercions by inserting an extra level of Query that effectively
+ * just does a projection.
*/
/*
{
/*
* For scalar-type returns, the target list must have exactly one
- * non-junk entry, and its type must agree with what the user
- * declared; except we allow binary-compatible types too.
+ * non-junk entry, and its type must be coercible to rettype.
*/
TargetEntry *tle;
tle = (TargetEntry *) linitial(tlist);
Assert(!tle->resjunk);
- restype = exprType((Node *) tle->expr);
- if (!IsBinaryCoercible(restype, rettype))
+ if (!coerce_fn_result_column(tle, rettype, -1,
+ tlist_is_modifiable,
+ &upper_tlist,
+ &upper_tlist_nontrivial))
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("return type mismatch in function declared to return %s",
format_type_be(rettype)),
errdetail("Actual return type is %s.",
- format_type_be(restype))));
- if (modifyTargetList && restype != rettype)
- {
- tle->expr = (Expr *) makeRelabelType(tle->expr,
- rettype,
- -1,
- get_typcollation(rettype),
- COERCE_IMPLICIT_CAST);
- /* Relabel is dangerous if TLE is a sort/group or setop column */
- if (tle->ressortgroupref != 0 || parse->setOperations)
- *modifyTargetList = true;
- }
-
- /* Set up junk filter if needed */
- if (junkFilter)
- *junkFilter = ExecInitJunkFilter(tlist,
- MakeSingleTupleTableSlot(NULL, &TTSOpsMinimalTuple));
+ format_type_be(exprType((Node *) tle->expr)))));
}
else if (fn_typtype == TYPTYPE_COMPOSITE || rettype == RECORDOID)
{
*
* Note that we will not consider a domain over composite to be a
* "rowtype" return type; it goes through the scalar case above. This
- * is because SQL functions don't provide any implicit casting to the
- * result type, so there is no way to produce a domain-over-composite
- * result except by computing it as an explicit single-column result.
+ * is because we only provide column-by-column implicit casting, and
+ * will not cast the complete record result. So the only way to
+ * produce a domain-over-composite result is to compute it as an
+ * explicit single-column result. The single-composite-column code
+ * path just below could handle such cases, but it won't be reached.
*/
- TupleDesc tupdesc;
int tupnatts; /* physical number of columns in tuple */
int tuplogcols; /* # of nondeleted columns in tuple */
int colindex; /* physical column index */
- List *newtlist; /* new non-junk tlist entries */
- List *junkattrs; /* new junk tlist entries */
/*
- * If the target list is of length 1, and the type of the varnode in
- * the target list matches the declared return type, this is okay.
- * This can happen, for example, where the body of the function is
- * 'SELECT func2()', where func2 has the same composite return type as
- * the function that's calling it.
+ * If the target list has one non-junk entry, and that expression has
+ * or can be coerced to the declared return type, take it as the
+ * result. This allows, for example, 'SELECT func2()', where func2
+ * has the same composite return type as the function that's calling
+ * it. This provision creates some ambiguity --- maybe the expression
+ * was meant to be the lone field of the composite result --- but it
+ * works well enough as long as we don't get too enthusiastic about
+ * inventing coercions from scalar to composite types.
*
- * XXX Note that if rettype is RECORD, the IsBinaryCoercible check
- * will succeed for any composite restype. For the moment we rely on
+ * XXX Note that if rettype is RECORD and the expression is of a named
+ * composite type, or vice versa, this coercion will succeed, whether
+ * or not the record type really matches. For the moment we rely on
* runtime type checking to catch any discrepancy, but it'd be nice to
* do better at parse time.
*/
TargetEntry *tle = (TargetEntry *) linitial(tlist);
Assert(!tle->resjunk);
- restype = exprType((Node *) tle->expr);
- if (IsBinaryCoercible(restype, rettype))
+ if (coerce_fn_result_column(tle, rettype, -1,
+ tlist_is_modifiable,
+ &upper_tlist,
+ &upper_tlist_nontrivial))
{
- if (modifyTargetList && restype != rettype)
- {
- tle->expr = (Expr *) makeRelabelType(tle->expr,
- rettype,
- -1,
- get_typcollation(rettype),
- COERCE_IMPLICIT_CAST);
- /* Relabel is dangerous if sort/group or setop column */
- if (tle->ressortgroupref != 0 || parse->setOperations)
- *modifyTargetList = true;
- }
- /* Set up junk filter if needed */
- if (junkFilter)
- {
- TupleTableSlot *slot =
- MakeSingleTupleTableSlot(NULL, &TTSOpsMinimalTuple);
-
- *junkFilter = ExecInitJunkFilter(tlist, slot);
- }
- return false; /* NOT returning whole tuple */
+ /* Note that we're NOT setting is_tuple_result */
+ goto tlist_coercion_finished;
}
}
/*
- * Is the rowtype fixed, or determined only at runtime? (Note we
- * cannot see TYPEFUNC_COMPOSITE_DOMAIN here.)
+ * If the caller didn't provide an expected tupdesc, we can't do any
+ * further checking. Assume we're returning the whole tuple.
*/
- if (get_func_result_type(func_id, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
+ if (rettupdesc == NULL)
{
- /*
- * Assume we are returning the whole tuple. Crosschecking against
- * what the caller expects will happen at runtime.
- */
- if (junkFilter)
- {
- TupleTableSlot *slot;
-
- slot = MakeSingleTupleTableSlot(NULL, &TTSOpsMinimalTuple);
- *junkFilter = ExecInitJunkFilter(tlist, slot);
- }
+ /* Return tlist if requested */
+ if (resultTargetList)
+ *resultTargetList = tlist;
return true;
}
- Assert(tupdesc);
/*
- * Verify that the targetlist matches the return tuple type. We scan
- * the non-deleted attributes to ensure that they match the datatypes
- * of the non-resjunk columns. For deleted attributes, insert NULL
- * result columns if the caller asked for that.
+ * Verify that the targetlist matches the return tuple type. We scan
+ * the non-resjunk columns, and coerce them if necessary to match the
+ * datatypes of the non-deleted attributes. For deleted attributes,
+ * insert NULL result columns if the caller asked for that.
*/
- tupnatts = tupdesc->natts;
+ tupnatts = rettupdesc->natts;
tuplogcols = 0; /* we'll count nondeleted cols as we go */
colindex = 0;
- newtlist = NIL; /* these are only used if modifyTargetList */
- junkattrs = NIL;
foreach(lc, tlist)
{
TargetEntry *tle = (TargetEntry *) lfirst(lc);
Form_pg_attribute attr;
- Oid tletype;
- Oid atttype;
+ /* resjunk columns can simply be ignored */
if (tle->resjunk)
- {
- if (modifyTargetList)
- junkattrs = lappend(junkattrs, tle);
continue;
- }
do
{
errmsg("return type mismatch in function declared to return %s",
format_type_be(rettype)),
errdetail("Final statement returns too many columns.")));
- attr = TupleDescAttr(tupdesc, colindex - 1);
- if (attr->attisdropped && modifyTargetList)
+ attr = TupleDescAttr(rettupdesc, colindex - 1);
+ if (attr->attisdropped && insertDroppedCols)
{
Expr *null_expr;
(Datum) 0,
true, /* isnull */
true /* byval */ );
- newtlist = lappend(newtlist,
- makeTargetEntry(null_expr,
- colindex,
- NULL,
- false));
- /* NULL insertion is dangerous in a setop */
- if (parse->setOperations)
- *modifyTargetList = true;
+ upper_tlist = lappend(upper_tlist,
+ makeTargetEntry(null_expr,
+ list_length(upper_tlist) + 1,
+ NULL,
+ false));
+ upper_tlist_nontrivial = true;
}
} while (attr->attisdropped);
tuplogcols++;
- tletype = exprType((Node *) tle->expr);
- atttype = attr->atttypid;
- if (!IsBinaryCoercible(tletype, atttype))
+ if (!coerce_fn_result_column(tle,
+ attr->atttypid, attr->atttypmod,
+ tlist_is_modifiable,
+ &upper_tlist,
+ &upper_tlist_nontrivial))
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("return type mismatch in function declared to return %s",
format_type_be(rettype)),
errdetail("Final statement returns %s instead of %s at column %d.",
- format_type_be(tletype),
- format_type_be(atttype),
+ format_type_be(exprType((Node *) tle->expr)),
+ format_type_be(attr->atttypid),
tuplogcols)));
- if (modifyTargetList)
- {
- if (tletype != atttype)
- {
- tle->expr = (Expr *) makeRelabelType(tle->expr,
- atttype,
- -1,
- get_typcollation(atttype),
- COERCE_IMPLICIT_CAST);
- /* Relabel is dangerous if sort/group or setop column */
- if (tle->ressortgroupref != 0 || parse->setOperations)
- *modifyTargetList = true;
- }
- tle->resno = colindex;
- newtlist = lappend(newtlist, tle);
- }
}
- /* remaining columns in tupdesc had better all be dropped */
+ /* remaining columns in rettupdesc had better all be dropped */
for (colindex++; colindex <= tupnatts; colindex++)
{
- if (!TupleDescAttr(tupdesc, colindex - 1)->attisdropped)
+ if (!TupleDescAttr(rettupdesc, colindex - 1)->attisdropped)
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("return type mismatch in function declared to return %s",
format_type_be(rettype)),
errdetail("Final statement returns too few columns.")));
- if (modifyTargetList)
+ if (insertDroppedCols)
{
Expr *null_expr;
(Datum) 0,
true, /* isnull */
true /* byval */ );
- newtlist = lappend(newtlist,
- makeTargetEntry(null_expr,
- colindex,
- NULL,
- false));
- /* NULL insertion is dangerous in a setop */
- if (parse->setOperations)
- *modifyTargetList = true;
+ upper_tlist = lappend(upper_tlist,
+ makeTargetEntry(null_expr,
+ list_length(upper_tlist) + 1,
+ NULL,
+ false));
+ upper_tlist_nontrivial = true;
}
}
- if (modifyTargetList)
- {
- /* ensure resjunk columns are numbered correctly */
- foreach(lc, junkattrs)
- {
- TargetEntry *tle = (TargetEntry *) lfirst(lc);
-
- tle->resno = colindex++;
- }
- /* replace the tlist with the modified one */
- *tlist_ptr = list_concat(newtlist, junkattrs);
- }
-
- /* Set up junk filter if needed */
- if (junkFilter)
- {
- TupleTableSlot *slot =
- MakeSingleTupleTableSlot(NULL, &TTSOpsMinimalTuple);
-
- *junkFilter = ExecInitJunkFilterConversion(tlist,
- CreateTupleDescCopy(tupdesc),
- slot);
- }
-
/* Report that we are returning entire tuple result */
- return true;
+ is_tuple_result = true;
}
else
ereport(ERROR,
errmsg("return type %s is not supported for SQL functions",
format_type_be(rettype))));
- return false;
+tlist_coercion_finished:
+
+ /*
+ * If necessary, modify the final Query by injecting an extra Query level
+ * that just performs a projection. (It'd be dubious to do this to a
+ * non-SELECT query, but we never have to; RETURNING lists can always be
+ * modified in-place.)
+ */
+ if (upper_tlist_nontrivial)
+ {
+ Query *newquery;
+ List *colnames;
+ RangeTblEntry *rte;
+ RangeTblRef *rtr;
+
+ Assert(parse->commandType == CMD_SELECT);
+
+ /* Most of the upper Query struct can be left as zeroes/nulls */
+ newquery = makeNode(Query);
+ newquery->commandType = CMD_SELECT;
+ newquery->querySource = parse->querySource;
+ newquery->canSetTag = true;
+ newquery->targetList = upper_tlist;
+
+ /* We need a moderately realistic colnames list for the subquery RTE */
+ colnames = NIL;
+ foreach(lc, parse->targetList)
+ {
+ TargetEntry *tle = (TargetEntry *) lfirst(lc);
+
+ if (tle->resjunk)
+ continue;
+ colnames = lappend(colnames,
+ makeString(tle->resname ? tle->resname : ""));
+ }
+
+ /* Build a suitable RTE for the subquery */
+ rte = makeNode(RangeTblEntry);
+ rte->rtekind = RTE_SUBQUERY;
+ rte->subquery = parse;
+ rte->eref = rte->alias = makeAlias("*SELECT*", colnames);
+ rte->lateral = false;
+ rte->inh = false;
+ rte->inFromCl = true;
+ newquery->rtable = list_make1(rte);
+
+ rtr = makeNode(RangeTblRef);
+ rtr->rtindex = 1;
+ newquery->jointree = makeFromExpr(list_make1(rtr), NULL);
+
+ /* Replace original query in the correct element of the query list */
+ lfirst(parse_cell) = newquery;
+ }
+
+ /* Return tlist (possibly modified) if requested */
+ if (resultTargetList)
+ *resultTargetList = upper_tlist;
+
+ return is_tuple_result;
+}
+
+/*
+ * Process one function result column for check_sql_fn_retval
+ *
+ * Coerce the output value to the required type/typmod, and add a column
+ * to *upper_tlist for it. Set *upper_tlist_nontrivial to true if we
+ * add an upper tlist item that's not just a Var.
+ *
+ * Returns true if OK, false if could not coerce to required type
+ * (in which case, no changes have been made)
+ */
+static bool
+coerce_fn_result_column(TargetEntry *src_tle,
+ Oid res_type,
+ int32 res_typmod,
+ bool tlist_is_modifiable,
+ List **upper_tlist,
+ bool *upper_tlist_nontrivial)
+{
+ TargetEntry *new_tle;
+ Expr *new_tle_expr;
+ Node *cast_result;
+
+ /*
+ * If the TLE has a sortgroupref marking, don't change it, as it probably
+ * is referenced by ORDER BY, DISTINCT, etc, and changing its type would
+ * break query semantics. Otherwise, it's safe to modify in-place unless
+ * the query as a whole has issues with that.
+ */
+ if (tlist_is_modifiable && src_tle->ressortgroupref == 0)
+ {
+ /* OK to modify src_tle in place, if necessary */
+ cast_result = coerce_to_target_type(NULL,
+ (Node *) src_tle->expr,
+ exprType((Node *) src_tle->expr),
+ res_type, res_typmod,
+ COERCION_ASSIGNMENT,
+ COERCE_IMPLICIT_CAST,
+ -1);
+ if (cast_result == NULL)
+ return false;
+ src_tle->expr = (Expr *) cast_result;
+ /* Make a Var referencing the possibly-modified TLE */
+ new_tle_expr = (Expr *) makeVarFromTargetEntry(1, src_tle);
+ }
+ else
+ {
+ /* Any casting must happen in the upper tlist */
+ Var *var = makeVarFromTargetEntry(1, src_tle);
+
+ cast_result = coerce_to_target_type(NULL,
+ (Node *) var,
+ var->vartype,
+ res_type, res_typmod,
+ COERCION_ASSIGNMENT,
+ COERCE_IMPLICIT_CAST,
+ -1);
+ if (cast_result == NULL)
+ return false;
+ /* Did the coercion actually do anything? */
+ if (cast_result != (Node *) var)
+ *upper_tlist_nontrivial = true;
+ new_tle_expr = (Expr *) cast_result;
+ }
+ new_tle = makeTargetEntry(new_tle_expr,
+ list_length(*upper_tlist) + 1,
+ src_tle->resname, false);
+ *upper_tlist = lappend(*upper_tlist, new_tle);
+ return true;
}
int nargs, List *args);
static Node *substitute_actual_srf_parameters_mutator(Node *node,
substitute_actual_srf_parameters_context *context);
-static bool tlist_matches_coltypelist(List *tlist, List *coltypelist);
/*****************************************************************************
char *src;
Datum tmp;
bool isNull;
- bool modifyTargetList;
MemoryContext oldcxt;
MemoryContext mycxt;
inline_error_callback_arg callback_arg;
ErrorContextCallback sqlerrcontext;
FuncExpr *fexpr;
SQLFunctionParseInfoPtr pinfo;
+ TupleDesc rettupdesc;
ParseState *pstate;
List *raw_parsetree_list;
+ List *querytree_list;
Query *querytree;
Node *newexpr;
int *usecounts;
/*
* Set up to handle parameters while parsing the function body. We need a
* dummy FuncExpr node containing the already-simplified arguments to pass
- * to prepare_sql_fn_parse_info. (It is really only needed if there are
- * some polymorphic arguments, but for simplicity we always build it.)
+ * to prepare_sql_fn_parse_info. (In some cases we don't really need
+ * that, but for simplicity we always build it.)
*/
fexpr = makeNode(FuncExpr);
fexpr->funcid = funcid;
(Node *) fexpr,
input_collid);
+ /* fexpr also provides a convenient way to resolve a composite result */
+ (void) get_expr_result_type((Node *) fexpr,
+ NULL,
+ &rettupdesc);
+
/*
* We just do parsing and parse analysis, not rewriting, because rewriting
* will not affect table-free-SELECT-only queries, which is all that we
* Make sure the function (still) returns what it's declared to. This
* will raise an error if wrong, but that's okay since the function would
* fail at runtime anyway. Note that check_sql_fn_retval will also insert
- * a RelabelType if needed to make the tlist expression match the declared
+ * a coercion if needed to make the tlist expression match the declared
* type of the function.
*
* Note: we do not try this until we have verified that no rewriting was
* needed; that's probably not important, but let's be careful.
*/
- if (check_sql_fn_retval(funcid, result_type, list_make1(querytree),
- &modifyTargetList, NULL))
+ querytree_list = list_make1(querytree);
+ if (check_sql_fn_retval(querytree_list, result_type, rettupdesc,
+ false, NULL))
goto fail; /* reject whole-tuple-result cases */
+ /*
+ * Given the tests above, check_sql_fn_retval shouldn't have decided to
+ * inject a projection step, but let's just make sure.
+ */
+ if (querytree != linitial(querytree_list))
+ goto fail;
+
/* Now we can grab the tlist expression */
newexpr = (Node *) ((TargetEntry *) linitial(querytree->targetList))->expr;
if (exprType(newexpr) != result_type)
goto fail;
- /* check_sql_fn_retval couldn't have made any dangerous tlist changes */
- Assert(!modifyTargetList);
-
/*
* Additional validity checks on the expression. It mustn't be more
* volatile than the surrounding function (this is to avoid breaking hacks
char *src;
Datum tmp;
bool isNull;
- bool modifyTargetList;
MemoryContext oldcxt;
MemoryContext mycxt;
inline_error_callback_arg callback_arg;
ErrorContextCallback sqlerrcontext;
SQLFunctionParseInfoPtr pinfo;
+ TypeFuncClass functypclass;
+ TupleDesc rettupdesc;
List *raw_parsetree_list;
List *querytree_list;
Query *querytree;
(Node *) fexpr,
fexpr->inputcollid);
+ /*
+ * Also resolve the actual function result tupdesc, if composite. If the
+ * function is just declared to return RECORD, dig the info out of the AS
+ * clause.
+ */
+ functypclass = get_expr_result_type((Node *) fexpr, NULL, &rettupdesc);
+ if (functypclass == TYPEFUNC_RECORD)
+ rettupdesc = BuildDescFromLists(rtfunc->funccolnames,
+ rtfunc->funccoltypes,
+ rtfunc->funccoltypmods,
+ rtfunc->funccolcollations);
+
/*
* Parse, analyze, and rewrite (unlike inline_function(), we can't skip
* rewriting here). We can fail as soon as we find more than one query,
* Make sure the function (still) returns what it's declared to. This
* will raise an error if wrong, but that's okay since the function would
* fail at runtime anyway. Note that check_sql_fn_retval will also insert
- * RelabelType(s) and/or NULL columns if needed to make the tlist
- * expression(s) match the declared type of the function.
+ * coercions if needed to make the tlist expression(s) match the declared
+ * type of the function. We also ask it to insert dummy NULL columns for
+ * any dropped columns in rettupdesc, so that the elements of the modified
+ * tlist match up to the attribute numbers.
*
* If the function returns a composite type, don't inline unless the check
* shows it's returning a whole tuple result; otherwise what it's
- * returning is a single composite column which is not what we need. (Like
- * check_sql_fn_retval, we deliberately exclude domains over composite
- * here.)
+ * returning is a single composite column which is not what we need.
*/
- if (!check_sql_fn_retval(func_oid, fexpr->funcresulttype,
- querytree_list,
- &modifyTargetList, NULL) &&
- (get_typtype(fexpr->funcresulttype) == TYPTYPE_COMPOSITE ||
- fexpr->funcresulttype == RECORDOID))
+ if (!check_sql_fn_retval(querytree_list,
+ fexpr->funcresulttype, rettupdesc,
+ true, NULL) &&
+ (functypclass == TYPEFUNC_COMPOSITE ||
+ functypclass == TYPEFUNC_COMPOSITE_DOMAIN ||
+ functypclass == TYPEFUNC_RECORD))
goto fail; /* reject not-whole-tuple-result cases */
/*
- * If we had to modify the tlist to make it match, and the statement is
- * one in which changing the tlist contents could change semantics, we
- * have to punt and not inline.
- */
- if (modifyTargetList)
- goto fail;
-
- /*
- * If it returns RECORD, we have to check against the column type list
- * provided in the RTE; check_sql_fn_retval can't do that. (If no match,
- * we just fail to inline, rather than complaining; see notes for
- * tlist_matches_coltypelist.) We don't have to do this for functions
- * with declared OUT parameters, even though their funcresulttype is
- * RECORDOID, so check get_func_result_type too.
+ * check_sql_fn_retval might've inserted a projection step, but that's
+ * fine; just make sure we use the upper Query.
*/
- if (fexpr->funcresulttype == RECORDOID &&
- get_func_result_type(func_oid, NULL, NULL) == TYPEFUNC_RECORD &&
- !tlist_matches_coltypelist(querytree->targetList,
- rtfunc->funccoltypes))
- goto fail;
+ querytree = linitial(querytree_list);
/*
* Looks good --- substitute parameters into the query.
substitute_actual_srf_parameters_mutator,
(void *) context);
}
-
-/*
- * Check whether a SELECT targetlist emits the specified column types,
- * to see if it's safe to inline a function returning record.
- *
- * We insist on exact match here. The executor allows binary-coercible
- * cases too, but we don't have a way to preserve the correct column types
- * in the correct places if we inline the function in such a case.
- *
- * Note that we only check type OIDs not typmods; this agrees with what the
- * executor would do at runtime, and attributing a specific typmod to a
- * function result is largely wishful thinking anyway.
- */
-static bool
-tlist_matches_coltypelist(List *tlist, List *coltypelist)
-{
- ListCell *tlistitem;
- ListCell *clistitem;
-
- clistitem = list_head(coltypelist);
- foreach(tlistitem, tlist)
- {
- TargetEntry *tle = (TargetEntry *) lfirst(tlistitem);
- Oid coltype;
-
- if (tle->resjunk)
- continue; /* ignore junk columns */
-
- if (clistitem == NULL)
- return false; /* too many tlist items */
-
- coltype = lfirst_oid(clistitem);
- clistitem = lnext(coltypelist, clistitem);
-
- if (exprType((Node *) tle->expr) != coltype)
- return false; /* column type mismatch */
- }
-
- if (clistitem != NULL)
- return false; /* too few tlist items */
-
- return true;
-}
ERROR: a column definition list is required for functions returning "record"
LINE 1: select * from array_to_set(array['one', 'two']);
^
+-- after-the-fact coercion of the columns is now possible, too
+select * from array_to_set(array['one', 'two']) as t(f1 numeric(4,2),f2 text);
+ f1 | f2
+------+-----
+ 1.00 | one
+ 2.00 | two
+(2 rows)
+
+-- and if it doesn't work, you get a compile-time not run-time error
+select * from array_to_set(array['one', 'two']) as t(f1 point,f2 text);
+ERROR: return type mismatch in function declared to return record
+DETAIL: Final statement returns integer instead of point at column 1.
+CONTEXT: SQL function "array_to_set" during startup
+-- with "strict", this function can't be inlined in FROM
+explain (verbose, costs off)
+ select * from array_to_set(array['one', 'two']) as t(f1 numeric(4,2),f2 text);
+ QUERY PLAN
+----------------------------------------------------
+ Function Scan on public.array_to_set t
+ Output: f1, f2
+ Function Call: array_to_set('{one,two}'::text[])
+(3 rows)
+
+-- but without, it can be:
+create or replace function array_to_set(anyarray) returns setof record as $$
+ select i AS "index", $1[i] AS "value" from generate_subscripts($1, 1) i
+$$ language sql immutable;
+select array_to_set(array['one', 'two']);
+ array_to_set
+--------------
+ (1,one)
+ (2,two)
+(2 rows)
+
+select * from array_to_set(array['one', 'two']) as t(f1 int,f2 text);
+ f1 | f2
+----+-----
+ 1 | one
+ 2 | two
+(2 rows)
+
+select * from array_to_set(array['one', 'two']) as t(f1 numeric(4,2),f2 text);
+ f1 | f2
+------+-----
+ 1.00 | one
+ 2.00 | two
+(2 rows)
+
+select * from array_to_set(array['one', 'two']) as t(f1 point,f2 text);
+ERROR: return type mismatch in function declared to return record
+DETAIL: Final statement returns integer instead of point at column 1.
+CONTEXT: SQL function "array_to_set" during inlining
+explain (verbose, costs off)
+ select * from array_to_set(array['one', 'two']) as t(f1 numeric(4,2),f2 text);
+ QUERY PLAN
+--------------------------------------------------------------
+ Function Scan on pg_catalog.generate_subscripts i
+ Output: i.i, ('{one,two}'::text[])[i.i]
+ Function Call: generate_subscripts('{one,two}'::text[], 1)
+(3 rows)
+
create temp table rngfunc(f1 int8, f2 int8);
create function testrngfunc() returns record as $$
insert into rngfunc values (1,2) returning *;
LINE 1: select * from testrngfunc();
^
drop function testrngfunc();
+-- Check that typmod imposed by a composite type is honored
+create type rngfunc_type as (f1 numeric(35,6), f2 numeric(35,2));
+create function testrngfunc() returns rngfunc_type as $$
+ select 7.136178319899999964, 7.136178319899999964;
+$$ language sql immutable;
+explain (verbose, costs off)
+select testrngfunc();
+ QUERY PLAN
+-------------------------------------------
+ Result
+ Output: '(7.136178,7.14)'::rngfunc_type
+(2 rows)
+
+select testrngfunc();
+ testrngfunc
+-----------------
+ (7.136178,7.14)
+(1 row)
+
+explain (verbose, costs off)
+select * from testrngfunc();
+ QUERY PLAN
+--------------------------------------------------
+ Function Scan on testrngfunc
+ Output: f1, f2
+ Function Call: '(7.136178,7.14)'::rngfunc_type
+(3 rows)
+
+select * from testrngfunc();
+ f1 | f2
+----------+------
+ 7.136178 | 7.14
+(1 row)
+
+create or replace function testrngfunc() returns rngfunc_type as $$
+ select 7.136178319899999964, 7.136178319899999964;
+$$ language sql volatile;
+explain (verbose, costs off)
+select testrngfunc();
+ QUERY PLAN
+-------------------------
+ Result
+ Output: testrngfunc()
+(2 rows)
+
+select testrngfunc();
+ testrngfunc
+-----------------
+ (7.136178,7.14)
+(1 row)
+
+explain (verbose, costs off)
+select * from testrngfunc();
+ QUERY PLAN
+-------------------------------------
+ Function Scan on public.testrngfunc
+ Output: f1, f2
+ Function Call: testrngfunc()
+(3 rows)
+
+select * from testrngfunc();
+ f1 | f2
+----------+------
+ 7.136178 | 7.14
+(1 row)
+
+drop function testrngfunc();
+create function testrngfunc() returns setof rngfunc_type as $$
+ select 7.136178319899999964, 7.136178319899999964;
+$$ language sql immutable;
+explain (verbose, costs off)
+select testrngfunc();
+ QUERY PLAN
+-------------------------
+ ProjectSet
+ Output: testrngfunc()
+ -> Result
+(3 rows)
+
+select testrngfunc();
+ testrngfunc
+-----------------
+ (7.136178,7.14)
+(1 row)
+
+explain (verbose, costs off)
+select * from testrngfunc();
+ QUERY PLAN
+--------------------------------------------------------
+ Result
+ Output: 7.136178::numeric(35,6), 7.14::numeric(35,2)
+(2 rows)
+
+select * from testrngfunc();
+ f1 | f2
+----------+------
+ 7.136178 | 7.14
+(1 row)
+
+create or replace function testrngfunc() returns setof rngfunc_type as $$
+ select 7.136178319899999964, 7.136178319899999964;
+$$ language sql volatile;
+explain (verbose, costs off)
+select testrngfunc();
+ QUERY PLAN
+-------------------------
+ ProjectSet
+ Output: testrngfunc()
+ -> Result
+(3 rows)
+
+select testrngfunc();
+ testrngfunc
+-----------------
+ (7.136178,7.14)
+(1 row)
+
+explain (verbose, costs off)
+select * from testrngfunc();
+ QUERY PLAN
+-------------------------------------
+ Function Scan on public.testrngfunc
+ Output: f1, f2
+ Function Call: testrngfunc()
+(3 rows)
+
+select * from testrngfunc();
+ f1 | f2
+----------+------
+ 7.136178 | 7.14
+(1 row)
+
+drop type rngfunc_type cascade;
+NOTICE: drop cascades to function testrngfunc()
--
-- Check some cases involving added/dropped columns in a rowtype result
--
drop function get_first_user();
drop function get_users();
drop table users;
--- this won't get inlined because of type coercion, but it shouldn't fail
+-- check behavior with type coercion required for a set-op
create or replace function rngfuncbar() returns setof text as
$$ select 'foo'::varchar union all select 'bar'::varchar ; $$
language sql stable;
bar
(2 rows)
+-- this function is now inlinable, too:
+explain (verbose, costs off) select * from rngfuncbar();
+ QUERY PLAN
+------------------------------------------------
+ Result
+ Output: ('foo'::character varying)
+ -> Append
+ -> Result
+ Output: 'foo'::character varying
+ -> Result
+ Output: 'bar'::character varying
+(7 rows)
+
drop function rngfuncbar();
-- check handling of a SQL function with multiple OUT params (bug #5777)
create or replace function rngfuncbar(out integer, out numeric) as
projects / users / rhaas / postgres.git / commitdiff