Code for WITHOUT OIDS.

On Wed, 2003-01-08 at 21:59, Christopher Kings-Lynne wrote:
> I agree.  I want to remove OIDs from heaps of our tables when we go to 7.3.
> I'd rather not have to do it in the dump due to down time.


Rod Taylor <rbt@rbt.ca>

doc/src/sgml/ref/alter_table.sgml

@@ -1,5 +1,5 @@
 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_table.sgml,v 1.54 2003/01/19 00:13:29 momjian Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_table.sgml,v 1.55 2003/02/13 05:19:59 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -33,6 +33,8 @@ ALTER TABLE [ ONLY ] <replaceable class="PARAMETER">table</replaceable> [ * ]
     ALTER [ COLUMN ] <replaceable class="PARAMETER">column</replaceable> SET STATISTICS <replaceable class="PARAMETER">integer</replaceable>
 ALTER TABLE [ ONLY ] <replaceable class="PARAMETER">table</replaceable> [ * ]
     ALTER [ COLUMN ] <replaceable class="PARAMETER">column</replaceable> SET STORAGE { PLAIN | EXTERNAL | EXTENDED | MAIN }
+ALTER TABLE [ ONLY ] <replaceable class="PARAMETER">table</replaceable> [ * ]
+    SET WITHOUT OIDS
 ALTER TABLE [ ONLY ] <replaceable class="PARAMETER">table</replaceable> [ * ]
     RENAME [ COLUMN ] <replaceable class="PARAMETER">column</replaceable> TO <replaceable
     class="PARAMETER">new_column</replaceable>
@@ -286,11 +288,24 @@ ALTER TABLE <replaceable class="PARAMETER">table</replaceable>
     </listitem>
    </varlistentry>
 
+   <varlistentry>
+    <term>SET WITHOUT OIDS</term>
+    <listitem>
+     <para>
+      Removes the <literal>OID</literal> column from the the table.  Removing (setting without)
+      oids from a table also do not occur immediately.  The space an <literal>OID</literal>
+      uses will be reclaimed when the tuple is updated.  Without updating the tuple, both the
+      space and the value of the <literal>OID</literal> are maintained indefinitely.  This is
+      semantically similar to the <literal>DROP COLUMN</literal> process.
+     </para>
+    </listitem>
+   </varlistentry>
+
    <varlistentry>
     <term>RENAME</term>
     <listitem>
      <para>
-      The <literal>RENAME</literal> forms change the name of  a table
+      The <literal>RENAME</literal> forms change the name of a table
       (or an index, sequence, or view) or the name of an individual column in
       a table. There is no effect on the stored data.
      </para>

src/backend/commands/tablecmds.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/commands/tablecmds.c,v 1.66 2003/02/09 06:56:26 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/commands/tablecmds.c,v 1.67 2003/02/13 05:19:59 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -2134,7 +2134,6 @@ AlterTableAlterColumnSetNotNull(Oid myrelid, bool recurse,
 	heap_close(rel, NoLock);
 }
 
-
 /*
  * ALTER TABLE ALTER COLUMN SET/DROP DEFAULT
  */
@@ -2384,6 +2383,122 @@ AlterTableAlterColumnFlags(Oid myrelid, bool recurse,
 	heap_close(rel, NoLock);	/* close rel, but keep lock! */
 }
 
+/*
+ * ALTER TABLE SET {WITHOUT} OIDS
+ */
+void
+AlterTableAlterOids(Oid myrelid, bool recurse, bool setOid)
+{
+	Relation	rel;
+	Relation	class_rel;
+	HeapTuple	tuple;
+	Form_pg_class tuple_class;
+
+	rel = heap_open(myrelid, AccessExclusiveLock);
+
+	if (rel->rd_rel->relkind != RELKIND_RELATION)
+		elog(ERROR, "ALTER TABLE: relation \"%s\" is not a table",
+			 RelationGetRelationName(rel));
+
+	if (!allowSystemTableMods
+		&& IsSystemRelation(rel))
+		elog(ERROR, "ALTER TABLE: relation \"%s\" is a system catalog",
+			 RelationGetRelationName(rel));
+
+	if (!pg_class_ownercheck(myrelid, GetUserId()))
+		aclcheck_error(ACLCHECK_NOT_OWNER, RelationGetRelationName(rel));
+
+
+	/* Get its pg_class tuple, too */
+	class_rel = heap_openr(RelationRelationName, RowExclusiveLock);
+
+	tuple = SearchSysCacheCopy(RELOID,
+							   ObjectIdGetDatum(myrelid),
+							   0, 0, 0);
+	if (!HeapTupleIsValid(tuple))
+		elog(ERROR, "ALTER TABLE: relation %u not found", myrelid);
+	tuple_class = (Form_pg_class) GETSTRUCT(tuple);
+
+	/* Can we change the ownership of this tuple? */
+	CheckTupleType(tuple_class);
+
+	/*
+	 * Okay, this is a valid tuple: check it's hasoids flag
+	 * to see if we actually need to change anything
+	 */
+	if (tuple_class->relhasoids == setOid)
+		elog(ERROR, "ALTER TABLE: Table is already %s",
+			 setOid ? "WITH OIDS" : "WITHOUT OIDS");
+
+	/*
+	 * Propagate to children if desired
+	 */
+	if (recurse)
+	{
+		List	   *child,
+				   *children;
+
+		/* this routine is actually in the planner */
+		children = find_all_inheritors(myrelid);
+
+		/*
+		 * find_all_inheritors does the recursive search of the
+		 * inheritance hierarchy, so all we have to do is process all of
+		 * the relids in the list that it returns.
+		 */
+		foreach(child, children)
+		{
+			Oid			childrelid = lfirsti(child);
+
+			if (childrelid == myrelid)
+				continue;
+
+			AlterTableAlterOids(childrelid, false, setOid);
+		}
+	}
+
+
+	tuple_class->relhasoids = setOid;
+	simple_heap_update(class_rel, &tuple->t_self, tuple);
+
+	/* Keep the catalog indexes up to date */
+	CatalogUpdateIndexes(class_rel, tuple);
+
+
+
+	if (setOid)
+		/*
+		 * TODO: Generate the now required OID pg_attribute entry
+		 */
+		elog(ERROR, "ALTER TABLE WITH OIDS is unsupported");
+	else
+	{
+		HeapTuple	atttup;
+		Relation	attrel;
+
+		/* Add / Remove the oid record from pg_attribute */
+		attrel = heap_open(RelOid_pg_attribute, RowExclusiveLock);
+
+		/*
+		 * Oids are being removed from the relation, so we need
+		 * to remove the oid pg_attribute record relating.
+		 */
+		atttup = SearchSysCache(ATTNUM,
+								ObjectIdGetDatum(myrelid),
+								ObjectIdAttributeNumber, 0, 0);
+		if (!HeapTupleIsValid(atttup))
+			elog(ERROR, "ALTER TABLE: relation %u doesn't have an Oid column to remove", myrelid);
+
+		simple_heap_delete(attrel, &atttup->t_self);
+
+		ReleaseSysCache(atttup);
+
+		heap_close(attrel, NoLock);		/* close rel, but keep lock! */
+	}
+
+	heap_close(rel, NoLock);		/* close rel, but keep lock! */
+	heap_close(class_rel, NoLock);	/* close rel, but keep lock! */
+}
 
 /*
  * ALTER TABLE DROP COLUMN

src/backend/parser/gram.y

@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.401 2003/02/10 04:44:45 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.402 2003/02/13 05:19:59 momjian Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -1132,7 +1132,7 @@ AlterTableStmt:
 			| ALTER TABLE relation_expr ALTER opt_column ColId SET NOT NULL_P
 				{
 					AlterTableStmt *n = makeNode(AlterTableStmt);
-					n->subtype = 'O';
+					n->subtype = 'n';
 					n->relation = $3;
 					n->name = $6;
 					$$ = (Node *)n;
@@ -1187,6 +1187,14 @@ AlterTableStmt:
 					n->behavior = $7;
 					$$ = (Node *)n;
 				}
+			/* ALTER TABLE <relation> SET WITHOUT OIDS  */
+			| ALTER TABLE relation_expr SET WITHOUT OIDS
+				{
+					AlterTableStmt *n = makeNode(AlterTableStmt);
+					n->relation = $3;
+					n->subtype = 'o';
+					$$ = (Node *)n;
+				}
 			/* ALTER TABLE <name> CREATE TOAST TABLE */
 			| ALTER TABLE qualified_name CREATE TOAST TABLE
 				{

src/backend/tcop/utility.c

@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/tcop/utility.c,v 1.191 2003/02/10 04:44:46 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/tcop/utility.c,v 1.192 2003/02/13 05:20:01 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -549,7 +549,7 @@ ProcessUtility(Node *parsetree,
 							  interpretInhOption(stmt->relation->inhOpt),
 														 stmt->name);
 						break;
-					case 'O':	/* ALTER COLUMN SET NOT NULL */
+					case 'n':	/* ALTER COLUMN SET NOT NULL */
 						AlterTableAlterColumnSetNotNull(relid,
 							  interpretInhOption(stmt->relation->inhOpt),
 														stmt->name);
@@ -611,6 +611,11 @@ ProcessUtility(Node *parsetree,
 						AlterTableOwner(relid,
 										get_usesysid(stmt->name));
 						break;
+					case 'o': /* ADD OIDS */
+						AlterTableAlterOids(relid,
+						 interpretInhOption(stmt->relation->inhOpt),
+											false);
+						break;
 					default:	/* oops */
 						elog(ERROR, "ProcessUtility: Invalid type for AlterTableStmt: %d",
 							 stmt->subtype);

src/include/commands/tablecmds.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: tablecmds.h,v 1.10 2002/11/11 22:19:24 tgl Exp $
+ * $Id: tablecmds.h,v 1.11 2003/02/13 05:20:03 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -47,6 +47,8 @@ extern void AlterTableCreateToastTable(Oid relOid, bool silent);
 
 extern void AlterTableOwner(Oid relationOid, int32 newOwnerSysId);
 
+extern void AlterTableAlterOids(Oid myrelid, bool recurse, bool setOid);
+
 extern Oid	DefineRelation(CreateStmt *stmt, char relkind);
 
 extern void RemoveRelation(const RangeVar *relation, DropBehavior behavior);

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 1.229 2003/02/10 04:44:47 tgl Exp $
+ * $Id: parsenodes.h,v 1.230 2003/02/13 05:20:03 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -698,7 +698,7 @@ typedef struct AlterTableStmt
 								 *	A = add column
 								 *	T = alter column default
 								 *	N = alter column drop not null
-								 *	O = alter column set not null
+								 *	n = alter column set not null
 								 *	S = alter column statistics
 								 *	M = alter column storage
 								 *	D = drop column
@@ -708,6 +708,7 @@ typedef struct AlterTableStmt
 								 *	X = drop constraint
 								 *	E = create toast table
 								 *	U = change owner
+								 *  o = DROP OIDS
 								 *------------
 								 */
 	RangeVar   *relation;		/* table to work on */

src/test/regress/expected/alter_table.out

@@ -1179,6 +1179,62 @@ order by relname, attnum;
 drop table p1, p2 cascade;
 NOTICE:  Drop cascades to table c1
 NOTICE:  Drop cascades to table gc1
+--
+-- Test the ALTER TABLE WITHOUT OIDS command
+--
+create table altstartwith (col integer) with oids;
+insert into altstartwith values (1);
+select oid > 0, * from altstartwith;
+ ?column? | col 
+----------+-----
+ t        |   1
+(1 row)
+
+alter table altstartwith set without oids;
+select oid > 0, * from altstartwith; -- fails
+ERROR:  Attribute "oid" not found
+select * from altstartwith;
+ col 
+-----
+   1
+(1 row)
+
+-- Run inheritance tests
+create table altwithoid (col integer) with oids;
+-- Inherits parents oid column
+create table altinhoid () inherits (altwithoid) without oids;
+insert into altinhoid values (1);
+select oid > 0, * from altwithoid;
+ ?column? | col 
+----------+-----
+ t        |   1
+(1 row)
+
+select oid > 0, * from altinhoid;
+ ?column? | col 
+----------+-----
+ t        |   1
+(1 row)
+
+alter table altwithoid set without oids;
+alter table altinhoid set without oids; -- fails
+ERROR:  ALTER TABLE: Table is already WITHOUT OIDS
+select oid > 0, * from altwithoid; -- fails
+ERROR:  Attribute "oid" not found
+select oid > 0, * from altinhoid; -- fails
+ERROR:  Attribute "oid" not found
+select * from altwithoid;
+ col 
+-----
+   1
+(1 row)
+
+select * from altinhoid;
+ col 
+-----
+   1
+(1 row)
+
 -- test renumbering of child-table columns in inherited operations
 create table p1 (f1 int);
 create table c1 (f2 text, f3 int) inherits (p1);

src/test/regress/sql/alter_table.sql

@@ -850,6 +850,39 @@ order by relname, attnum;
 
 drop table p1, p2 cascade;
 
+--
+-- Test the ALTER TABLE WITHOUT OIDS command
+--
+create table altstartwith (col integer) with oids;
+
+insert into altstartwith values (1);
+
+select oid > 0, * from altstartwith;
+
+alter table altstartwith set without oids;
+
+select oid > 0, * from altstartwith; -- fails
+select * from altstartwith;
+
+-- Run inheritance tests
+create table altwithoid (col integer) with oids;
+
+-- Inherits parents oid column
+create table altinhoid () inherits (altwithoid) without oids;
+
+insert into altinhoid values (1);
+
+select oid > 0, * from altwithoid;
+select oid > 0, * from altinhoid;
+
+alter table altwithoid set without oids;
+alter table altinhoid set without oids; -- fails
+
+select oid > 0, * from altwithoid; -- fails
+select oid > 0, * from altinhoid; -- fails
+select * from altwithoid;
+select * from altinhoid;
+
 -- test renumbering of child-table columns in inherited operations
 
 create table p1 (f1 int);