<!--
-$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_table.sgml,v 1.56 2003/02/19 04:06:28 momjian Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_table.sgml,v 1.57 2003/03/20 18:52:47 momjian Exp $
PostgreSQL documentation
-->
DROP CONSTRAINT <replaceable class="PARAMETER">constraint_name</replaceable> [ RESTRICT | CASCADE ]
ALTER TABLE <replaceable class="PARAMETER">table</replaceable>
OWNER TO <replaceable class="PARAMETER">new_owner</replaceable>
+ALTER TABLE <replaceable class="PARAMETER">table</replaceable>
+ CLUSTER ON <replaceable class="PARAMETER">index_name</replaceable>
</synopsis>
<refsect2 id="R2-SQL-ALTERTABLE-1">
</varlistentry>
<varlistentry>
+ <term><replaceable class="PARAMETER"> index_name </replaceable></term>
+ <listitem>
+ <para>
+ The index name on which the table should be marked for clustering.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
<term>CASCADE</term>
<listitem>
<para>
</listitem>
</varlistentry>
+ <varlistentry>
+ <term>CLUSTER</term>
+ <listitem>
+ <para>
+ This form marks a table for future <xref linkend="SQL-CLUSTER" endterm="sql-cluster-title">
+ operations.
+ </para>
+ </listitem>
+ </varlistentry>
+
</variablelist>
<para>
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/commands/tablecmds.c,v 1.68 2003/03/20 03:34:55 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/commands/tablecmds.c,v 1.69 2003/03/20 18:52:47 momjian Exp $
*
*-------------------------------------------------------------------------
*/
}
/*
+ * ALTER TABLE CLUSTER ON
+ *
+ * The only thing we have to do is to change the indisclustered bits.
+ */
+void
+AlterTableClusterOn(Oid relOid, const char *indexName)
+{
+ Relation rel,
+ pg_index;
+ List *index;
+ Oid indexOid;
+ HeapTuple indexTuple;
+ Form_pg_index indexForm;
+
+ rel = heap_open(relOid, AccessExclusiveLock);
+
+ indexOid = get_relname_relid(indexName, rel->rd_rel->relnamespace);
+
+ if (!OidIsValid(indexOid))
+ elog(ERROR, "ALTER TABLE: cannot find index \"%s\" for table \"%s\"",
+ indexName, NameStr(rel->rd_rel->relname));
+
+ 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);
+
+ /*
+ * If this is the same index the relation was previously
+ * clustered on, no need to do anything.
+ */
+ if (indexForm->indisclustered)
+ {
+ elog(NOTICE, "ALTER TABLE: table \"%s\" is already being clustered on index \"%s\"",
+ NameStr(rel->rd_rel->relname), indexName);
+ heap_close(rel, AccessExclusiveLock);
+ return;
+ }
+
+ pg_index = heap_openr(IndexRelationName, RowExclusiveLock);
+
+ /*
+ * Now check each index in the relation and set the bit where needed.
+ */
+ foreach (index, RelationGetIndexList(rel))
+ {
+ HeapTuple idxtuple;
+ Form_pg_index idxForm;
+
+ indexOid = lfirsto(index);
+ idxtuple = SearchSysCacheCopy(INDEXRELID,
+ ObjectIdGetDatum(indexOid),
+ 0, 0, 0);
+ if (!HeapTupleIsValid(idxtuple))
+ elog(ERROR, "Cache lookup failed for index %u", indexOid);
+ idxForm = (Form_pg_index) GETSTRUCT(idxtuple);
+ /*
+ * Unset the bit if set. We know it's wrong because we checked
+ * this earlier.
+ */
+ if (idxForm->indisclustered)
+ {
+ idxForm->indisclustered = false;
+ simple_heap_update(pg_index, &idxtuple->t_self, idxtuple);
+ CatalogUpdateIndexes(pg_index, idxtuple);
+ }
+ else if (idxForm->indexrelid == indexForm->indexrelid)
+ {
+ idxForm->indisclustered = true;
+ simple_heap_update(pg_index, &idxtuple->t_self, idxtuple);
+ CatalogUpdateIndexes(pg_index, idxtuple);
+ }
+ heap_freetuple(idxtuple);
+ }
+ ReleaseSysCache(indexTuple);
+ heap_close(rel, AccessExclusiveLock);
+ heap_close(pg_index, RowExclusiveLock);
+}
+
+/*
* ALTER TABLE CREATE TOAST TABLE
*/
void
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.407 2003/03/20 07:02:08 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.408 2003/03/20 18:52:47 momjian Exp $
*
* HISTORY
* AUTHOR DATE MAJOR EVENT
n->name = $6;
$$ = (Node *)n;
}
+ /* ALTER TABLE <name> CLUSTER ON <indexname> */
+ | ALTER TABLE qualified_name CLUSTER ON name
+ {
+ AlterTableStmt *n = makeNode(AlterTableStmt);
+ n->subtype = 'L';
+ n->relation = $3;
+ n->name = $6;
+ $$ = (Node *)n;
+ }
;
alter_column_default:
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/tcop/utility.c,v 1.196 2003/03/20 07:02:11 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/tcop/utility.c,v 1.197 2003/03/20 18:52:48 momjian Exp $
*
*-------------------------------------------------------------------------
*/
AlterTableOwner(relid,
get_usesysid(stmt->name));
break;
+ case 'L': /* CLUSTER ON */
+ AlterTableClusterOn(relid, stmt->name);
+ break;
case 'o': /* ADD OIDS */
AlterTableAlterOids(relid,
interpretInhOption(stmt->relation->inhOpt),
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $Id: tablecmds.h,v 1.11 2003/02/13 05:20:03 momjian Exp $
+ * $Id: tablecmds.h,v 1.12 2003/03/20 18:52:48 momjian Exp $
*
*-------------------------------------------------------------------------
*/
const char *constrName,
DropBehavior behavior);
+extern void AlterTableClusterOn(Oid relOid, const char *indexName);
+
extern void AlterTableCreateToastTable(Oid relOid, bool silent);
extern void AlterTableOwner(Oid relationOid, int32 newOwnerSysId);
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $Id: parsenodes.h,v 1.234 2003/03/20 07:02:11 momjian Exp $
+ * $Id: parsenodes.h,v 1.235 2003/03/20 18:52:48 momjian Exp $
*
*-------------------------------------------------------------------------
*/
* X = drop constraint
* E = create toast table
* U = change owner
+ * L = CLUSTER ON
* o = DROP OIDS
*------------
*/
clstr_tst_c
(1 row)
+-- Try changing indisclustered
+ALTER TABLE clstr_tst CLUSTER ON clstr_tst_b_c;
+SELECT pg_class.relname FROM pg_index, pg_class, pg_class AS pg_class_2
+WHERE pg_class.oid=indexrelid
+ AND indrelid=pg_class_2.oid
+ AND pg_class_2.relname = 'clstr_tst'
+ AND indisclustered;
+ relname
+---------------
+ clstr_tst_b_c
+(1 row)
+
-- Verify that clustering all tables does in fact cluster the right ones
CREATE USER clstr_user;
CREATE TABLE clstr_1 (a INT PRIMARY KEY);
AND pg_class_2.relname = 'clstr_tst'
AND indisclustered;
+-- Try changing indisclustered
+ALTER TABLE clstr_tst CLUSTER ON clstr_tst_b_c;
+SELECT pg_class.relname FROM pg_index, pg_class, pg_class AS pg_class_2
+WHERE pg_class.oid=indexrelid
+ AND indrelid=pg_class_2.oid
+ AND pg_class_2.relname = 'clstr_tst'
+ AND indisclustered;
+
-- Verify that clustering all tables does in fact cluster the right ones
CREATE USER clstr_user;
CREATE TABLE clstr_1 (a INT PRIMARY KEY);
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