diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml
index 6166b263345..255317883bc 100644
--- a/doc/src/sgml/ref/alter_table.sgml
+++ b/doc/src/sgml/ref/alter_table.sgml
@@ -76,6 +76,7 @@ ALTER TABLE [ IF EXISTS ] name
SET WITHOUT CLUSTER
SET WITHOUT OIDS
SET TABLESPACE new_tablespace
+ SET ACCESS METHOD new_access_method
SET { LOGGED | UNLOGGED }
SET ( storage_parameter [= value] [, ... ] )
RESET ( storage_parameter [, ... ] )
@@ -706,6 +707,16 @@ WITH ( MODULUS numeric_literal, REM
+
+ SET ACCESS METHOD
+
+
+ This form changes the access method of the table. See for more information.
+
+
+
+
SET { LOGGED | UNLOGGED }
@@ -1219,6 +1230,15 @@ WITH ( MODULUS numeric_literal, REM
+
+ new_access_method
+
+
+ The name of the access method to which the table will be converted.
+
+
+
+
new_schema
diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c
index 6487a9e3fcb..e0c84d649ee 100644
--- a/src/backend/commands/cluster.c
+++ b/src/backend/commands/cluster.c
@@ -597,6 +597,7 @@ rebuild_relation(Relation OldHeap, Oid indexOid, bool verbose)
/* Create the transient table that will receive the re-ordered data */
OIDNewHeap = make_new_heap(tableOid, tableSpace,
+ OldHeap->rd_rel->relam,
relpersistence,
AccessExclusiveLock);
@@ -626,8 +627,8 @@ rebuild_relation(Relation OldHeap, Oid indexOid, bool verbose)
* data, then call finish_heap_swap to complete the operation.
*/
Oid
-make_new_heap(Oid OIDOldHeap, Oid NewTableSpace, char relpersistence,
- LOCKMODE lockmode)
+make_new_heap(Oid OIDOldHeap, Oid NewTableSpace, Oid NewAccessMethod,
+ char relpersistence, LOCKMODE lockmode)
{
TupleDesc OldHeapDesc;
char NewHeapName[NAMEDATALEN];
@@ -686,7 +687,7 @@ make_new_heap(Oid OIDOldHeap, Oid NewTableSpace, char relpersistence,
InvalidOid,
InvalidOid,
OldHeap->rd_rel->relowner,
- OldHeap->rd_rel->relam,
+ NewAccessMethod,
OldHeapDesc,
NIL,
RELKIND_RELATION,
@@ -1036,6 +1037,10 @@ swap_relation_files(Oid r1, Oid r2, bool target_is_pg_class,
relform1->reltablespace = relform2->reltablespace;
relform2->reltablespace = swaptemp;
+ swaptemp = relform1->relam;
+ relform1->relam = relform2->relam;
+ relform2->relam = swaptemp;
+
swptmpchr = relform1->relpersistence;
relform1->relpersistence = relform2->relpersistence;
relform2->relpersistence = swptmpchr;
diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c
index 172ec6e9828..1ebd02fd684 100644
--- a/src/backend/commands/matview.c
+++ b/src/backend/commands/matview.c
@@ -298,8 +298,9 @@ ExecRefreshMatView(RefreshMatViewStmt *stmt, const char *queryString,
* it against access by any other process until commit (by which time it
* will be gone).
*/
- OIDNewHeap = make_new_heap(matviewOid, tableSpace, relpersistence,
- ExclusiveLock);
+ OIDNewHeap = make_new_heap(matviewOid, tableSpace,
+ matviewRel->rd_rel->relam,
+ relpersistence, ExclusiveLock);
LockRelationOid(OIDNewHeap, AccessExclusiveLock);
dest = CreateTransientRelDestReceiver(OIDNewHeap);
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 0da61784d7a..be91a00a170 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -177,6 +177,7 @@ typedef struct AlteredTableInfo
List *afterStmts; /* List of utility command parsetrees */
bool verify_new_notnull; /* T if we should recheck NOT NULL */
int rewrite; /* Reason for forced rewrite, if any */
+ Oid newAccessMethod; /* new access method; 0 means no change */
Oid newTableSpace; /* new tablespace; 0 means no change */
bool chgPersistence; /* T if SET LOGGED/UNLOGGED is used */
char newrelpersistence; /* if above is true */
@@ -540,6 +541,7 @@ static void change_owner_recurse_to_sequences(Oid relationOid,
static ObjectAddress ATExecClusterOn(Relation rel, const char *indexName,
LOCKMODE lockmode);
static void ATExecDropCluster(Relation rel, LOCKMODE lockmode);
+static void ATPrepSetAccessMethod(AlteredTableInfo *tab, Relation rel, const char *amname);
static bool ATPrepChangePersistence(Relation rel, bool toLogged);
static void ATPrepSetTableSpace(AlteredTableInfo *tab, Relation rel,
const char *tablespacename, LOCKMODE lockmode);
@@ -4287,6 +4289,7 @@ AlterTableGetLockLevel(List *cmds)
cmd_lockmode = ShareUpdateExclusiveLock;
break;
+ case AT_SetAccessMethod:
case AT_SetLogged:
case AT_SetUnLogged:
cmd_lockmode = AccessExclusiveLock;
@@ -4609,6 +4612,15 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
/* No command-specific prep needed */
pass = AT_PASS_MISC;
break;
+ case AT_SetAccessMethod: /* SET ACCESS METHOD */
+ ATSimplePermissions(rel, ATT_TABLE | ATT_MATVIEW);
+ if (tab->newAccessMethod)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("cannot change access method setting twice")));
+ ATPrepSetAccessMethod(tab, rel, cmd->name);
+ pass = AT_PASS_MISC;
+ break;
case AT_SetLogged: /* SET LOGGED */
ATSimplePermissions(rel, ATT_TABLE);
if (tab->chgPersistence)
@@ -5012,6 +5024,8 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab,
case AT_DropCluster: /* SET WITHOUT CLUSTER */
ATExecDropCluster(rel, lockmode);
break;
+ case AT_SetAccessMethod: /* SET ACCESS METHOD */
+ break;
case AT_SetLogged: /* SET LOGGED */
case AT_SetUnLogged: /* SET UNLOGGED */
break;
@@ -5365,6 +5379,7 @@ ATRewriteTables(AlterTableStmt *parsetree, List **wqueue, LOCKMODE lockmode,
Relation OldHeap;
Oid OIDNewHeap;
Oid NewTableSpace;
+ Oid accessmethod;
char persistence;
OldHeap = table_open(tab->relid, NoLock);
@@ -5411,6 +5426,13 @@ ATRewriteTables(AlterTableStmt *parsetree, List **wqueue, LOCKMODE lockmode,
persistence = tab->chgPersistence ?
tab->newrelpersistence : OldHeap->rd_rel->relpersistence;
+ /*
+ * Select access method of transient table (same as original
+ * unless user requested a change)
+ */
+ accessmethod = OidIsValid(tab->newAccessMethod) ?
+ tab->newAccessMethod : OldHeap->rd_rel->relam;
+
table_close(OldHeap, NoLock);
/*
@@ -5443,8 +5465,8 @@ ATRewriteTables(AlterTableStmt *parsetree, List **wqueue, LOCKMODE lockmode,
* persistence. That wouldn't work for pg_class, but that can't be
* unlogged anyway.
*/
- OIDNewHeap = make_new_heap(tab->relid, NewTableSpace, persistence,
- lockmode);
+ OIDNewHeap = make_new_heap(tab->relid, NewTableSpace, accessmethod,
+ persistence, lockmode);
/*
* Copy the heap data into the new table with the desired
@@ -15695,6 +15717,34 @@ ATExecSetCompression(AlteredTableInfo *tab,
}
+/*
+ * Preparation phase for SET TABLESPACE
+ *
+ * Check that access method exists. If it's the same as the table's current
+ * access method, it's a no-op. Otherwise, a table rewrite is necessary.
+ */
+static void
+ATPrepSetAccessMethod(AlteredTableInfo *tab, Relation rel, const char *amname)
+{
+ Oid amoid;
+
+ /* Check that the table access method exists */
+ amoid = get_table_am_oid(amname, false);
+
+ if (rel->rd_rel->relam == amoid)
+ return;
+
+ /* Save info for Phase 3 to do the real work */
+ if (OidIsValid(tab->newAccessMethod))
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("cannot have multiple SET ACCESS METHOD subcommands")));
+
+ tab->rewrite |= AT_REWRITE_ACCESS_METHOD;
+ tab->newAccessMethod = amoid;
+}
+
+
/*
* Preparation phase for SET LOGGED/UNLOGGED
*
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index b4ab4014c87..9e41e84b64c 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -2475,6 +2475,14 @@ alter_table_cmd:
n->name = NULL;
$$ = (Node *)n;
}
+ /* ALTER TABLE SET ACCESS METHOD */
+ | SET ACCESS METHOD name
+ {
+ AlterTableCmd *n = makeNode(AlterTableCmd);
+ n->subtype = AT_SetAccessMethod;
+ n->name = $4;
+ $$ = (Node *)n;
+ }
/* ALTER TABLE SET LOGGED */
| SET LOGGED
{
diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h
index a941f2accda..b64d3bc2040 100644
--- a/src/include/commands/cluster.h
+++ b/src/include/commands/cluster.h
@@ -35,8 +35,8 @@ extern void check_index_is_clusterable(Relation OldHeap, Oid indexOid,
bool recheck, LOCKMODE lockmode);
extern void mark_index_clustered(Relation rel, Oid indexOid, bool is_internal);
-extern Oid make_new_heap(Oid OIDOldHeap, Oid NewTableSpace, char relpersistence,
- LOCKMODE lockmode);
+extern Oid make_new_heap(Oid OIDOldHeap, Oid NewTableSpace, Oid NewAccessMethod,
+ char relpersistence, LOCKMODE lockmode);
extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap,
bool is_system_catalog,
bool swap_toast_by_content,
diff --git a/src/include/commands/event_trigger.h b/src/include/commands/event_trigger.h
index c11bf2d7810..e765e67fd10 100644
--- a/src/include/commands/event_trigger.h
+++ b/src/include/commands/event_trigger.h
@@ -32,6 +32,7 @@ typedef struct EventTriggerData
#define AT_REWRITE_ALTER_PERSISTENCE 0x01
#define AT_REWRITE_DEFAULT_VAL 0x02
#define AT_REWRITE_COLUMN_REWRITE 0x04
+#define AT_REWRITE_ACCESS_METHOD 0x08
/*
* EventTriggerData is the node type that is passed as fmgr "context" info
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index 615dfa26aa2..cce5c0834ee 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -1898,6 +1898,7 @@ typedef enum AlterTableType
AT_ChangeOwner, /* change owner */
AT_ClusterOn, /* CLUSTER ON */
AT_DropCluster, /* SET WITHOUT CLUSTER */
+ AT_SetAccessMethod, /* SET ACCESS METHOD */
AT_SetLogged, /* SET LOGGED */
AT_SetUnLogged, /* SET UNLOGGED */
AT_DropOids, /* SET WITHOUT OIDS */