The following patch was sent to the patches list:

This patch forces the use of 'DROP VIEW' to destroy views.

It also changes the syntax of DROP VIEW to
DROP VIEW v1, v2, ...
to match the syntax of DROP TABLE.

Some error messages were changed so this patch also includes changes to the
appropriate expected/*.out files.

Doc changes for 'DROP TABLE" and 'DROP VIEW' are included.


--
Mark Hollomon

1 files changed, 128 insertions, 79 deletions

diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index 6c0b2be5ea9..d63a5c6b7e2 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/tcop/utility.c,v 1.96 2000/10/16 17:08:07 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/tcop/utility.c,v 1.97 2000/10/18 16:16:06 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -46,6 +46,71 @@
 #include "utils/syscache.h"
 
 
+/*
+ *
+ */
+
+struct kindstrings {
+	char kind;
+	char *name;
+	char *command;
+};
+
+static struct kindstrings kindstringarray[] = {
+	{ RELKIND_RELATION, "table", "TABLE" },
+	{ RELKIND_SEQUENCE, "sequence", "SEQUENCE" },
+	{ RELKIND_VIEW, "view", "VIEW" },
+	{ RELKIND_INDEX, "index", "INDEX" },
+	{ '\0', "", "" }
+};
+
+
+static void
+DropErrorMsg(char* relname, char wrongkind, char rightkind)
+{
+	struct kindstrings *rentry;
+	struct kindstrings *wentry;
+
+	for (rentry = kindstringarray; rentry->kind != '\0'; rentry++)
+		if (rentry->kind == rightkind)
+			break;
+	Assert(rentry->kind != '\0');
+
+	for (wentry = kindstringarray; wentry->kind != '\0'; wentry++)
+		if (wentry->kind == wrongkind)
+			break;
+	Assert(wentry->kind != '\0');
+	
+	elog(ERROR, "%s is not a %s. Use 'DROP %s' to remove a %s",
+			relname, rentry->name, wentry->command, wentry->name);
+}
+
+static void
+CheckClassKind(char *name, char rightkind)
+{
+	HeapTuple	tuple;
+	struct kindstrings *rentry;
+	Form_pg_class classform;
+
+	tuple = SearchSysCacheTuple(RELNAME,
+								PointerGetDatum(name),
+								0, 0, 0);
+
+	if (!HeapTupleIsValid(tuple))
+	{
+		for (rentry = kindstringarray; rentry->kind != '\0'; rentry++)
+			if (rentry->kind == rightkind)
+				break;
+		Assert(rentry->kind != '\0');
+		elog(ERROR, "%s \"%s\" is nonexistent", rentry->name, name);
+	}
+
+	classform = (Form_pg_class) GETSTRUCT(tuple);
+
+	if (classform->relkind != rightkind)
+		DropErrorMsg(name, classform->relkind, rightkind);
+}
+
 /* ----------------
  *		general utility function invoker
  * ----------------
@@ -149,41 +214,76 @@ ProcessUtility(Node *parsetree,
 		case T_DropStmt:
 			{
 				DropStmt   *stmt = (DropStmt *) parsetree;
-				List	   *args = stmt->relNames;
+				List	   *args = stmt->names;
 				List	   *arg;
 
-				set_ps_display(commandTag = "DROP");
-
-				/* check as much as we can before we start dropping ... */
-				foreach(arg, args)
-				{
-					Relation	rel;
+				foreach(arg, args) {
 
 					relname = strVal(lfirst(arg));
 					if (!allowSystemTableMods && IsSystemRelationName(relname))
 						elog(ERROR, "class \"%s\" is a system catalog",
 							 relname);
-					rel = heap_openr(relname, AccessExclusiveLock);
-					if (stmt->sequence &&
-						rel->rd_rel->relkind != RELKIND_SEQUENCE)
-						elog(ERROR, "Use DROP TABLE to drop table '%s'",
-							 relname);
-					if (!(stmt->sequence) &&
-						rel->rd_rel->relkind == RELKIND_SEQUENCE)
-						elog(ERROR, "Use DROP SEQUENCE to drop sequence '%s'",
-							 relname);
-					/* close rel, but keep lock until end of xact */
-					heap_close(rel, NoLock);
-					if (!pg_ownercheck(GetUserId(), relname, RELNAME))
-						elog(ERROR, "you do not own class \"%s\"",
-							 relname);
-				}
-				/* OK, terminate 'em all */
-				foreach(arg, args)
-				{
-					relname = strVal(lfirst(arg));
-					RemoveRelation(relname);
+
+					set_ps_display(commandTag = "DROP");
+
+					switch(stmt->removeType)
+					{
+						case DROP_TABLE:
+							CheckClassKind(relname, RELKIND_RELATION);
+							if (!pg_ownercheck(GetUserId(), relname, RELNAME))
+								elog(ERROR, "you do not own table \"%s\"",
+									 relname);
+							RemoveRelation(relname);
+
+							break;
+
+						case DROP_SEQUENCE:
+							CheckClassKind(relname, RELKIND_SEQUENCE);
+							if (!pg_ownercheck(GetUserId(), relname, RELNAME))
+								elog(ERROR, "you do not own sequence \"%s\"",
+									 relname);
+							RemoveRelation(relname);
+
+							break;
+
+						case DROP_VIEW:
+							CheckClassKind(relname, RELKIND_VIEW);
+							if (!pg_ownercheck(GetUserId(), relname, RELNAME))
+								elog(ERROR, "you do not own view \"%s\"",
+									 relname);
+							RemoveView(relname);
+
+							break;
+
+						case DROP_INDEX:
+							CheckClassKind(relname, RELKIND_INDEX);
+							if (!pg_ownercheck(GetUserId(), relname, RELNAME))
+								elog(ERROR, "%s: %s", relname, 
+										aclcheck_error_strings[ACLCHECK_NOT_OWNER]);
+							RemoveIndex(relname);
+
+							break;
+
+						case DROP_RULE:
+							{
+								char	   *rulename = relname;
+								int			aclcheck_result;
+
+								relationName = RewriteGetRuleEventRel(rulename);
+								aclcheck_result = pg_aclcheck(relationName, GetUserId(), ACL_RU);
+								if (aclcheck_result != ACLCHECK_OK)
+									elog(ERROR, "%s: %s", relationName, 
+											aclcheck_error_strings[aclcheck_result]);
+								RemoveRewriteRule(rulename);
+							}
+							break;
+
+						case DROP_TYPE_P:
+							RemoveType(relname);
+							break;
+					}
 				}
+
 			}
 			break;
 
@@ -452,57 +552,6 @@ ProcessUtility(Node *parsetree,
 			}
 			break;
 
-		case T_RemoveStmt:
-			{
-				RemoveStmt *stmt = (RemoveStmt *) parsetree;
-
-				set_ps_display(commandTag = "DROP");
-
-				switch (stmt->removeType)
-				{
-					case INDEX:
-						relname = stmt->name;
-						if (!allowSystemTableMods && IsSystemRelationName(relname))
-							elog(ERROR, "class \"%s\" is a system catalog index",
-								 relname);
-						if (!pg_ownercheck(GetUserId(), relname, RELNAME))
-							elog(ERROR, "%s: %s", relname, aclcheck_error_strings[ACLCHECK_NOT_OWNER]);
-						RemoveIndex(relname);
-						break;
-					case RULE:
-						{
-							char	   *rulename = stmt->name;
-							int			aclcheck_result;
-
-							relationName = RewriteGetRuleEventRel(rulename);
-							aclcheck_result = pg_aclcheck(relationName, GetUserId(), ACL_RU);
-							if (aclcheck_result != ACLCHECK_OK)
-								elog(ERROR, "%s: %s", relationName, aclcheck_error_strings[aclcheck_result]);
-							RemoveRewriteRule(rulename);
-						}
-						break;
-					case TYPE_P:
-						/* XXX moved to remove.c */
-						RemoveType(stmt->name);
-						break;
-					case VIEW:
-						{
-							char	   *viewName = stmt->name;
-							char	   *ruleName;
-
-							ruleName = MakeRetrieveViewRuleName(viewName);
-							relationName = RewriteGetRuleEventRel(ruleName);
-							if (!pg_ownercheck(GetUserId(), relationName, RELNAME))
-								elog(ERROR, "%s: %s", relationName, aclcheck_error_strings[ACLCHECK_NOT_OWNER]);
-							pfree(ruleName);
-							RemoveView(viewName);
-						}
-						break;
-				}
-				break;
-			}
-			break;
-
 		case T_RemoveAggrStmt:
 			{
 				RemoveAggrStmt *stmt = (RemoveAggrStmt *) parsetree;