diff options
Diffstat (limited to 'src/backend/commands/tablecmds.c')
| -rw-r--r-- | src/backend/commands/tablecmds.c | 66 |
1 files changed, 63 insertions, 3 deletions
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index a16e7495067..fcd778c62a5 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -176,6 +176,7 @@ 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 */ @@ -538,6 +539,7 @@ 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); @@ -4096,6 +4098,7 @@ AlterTableGetLockLevel(List *cmds) */ case AT_AddColumn: /* may rewrite heap, in some cases and visible * to SELECT */ + case AT_SetAccessMethod: /* must rewrite heap */ case AT_SetTableSpace: /* must rewrite heap */ case AT_AlterColumnType: /* must rewrite heap */ cmd_lockmode = AccessExclusiveLock; @@ -4622,6 +4625,24 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd, ATSimplePermissions(cmd->subtype, rel, ATT_TABLE | ATT_FOREIGN_TABLE); pass = AT_PASS_DROP; break; + case AT_SetAccessMethod: /* SET ACCESS METHOD */ + ATSimplePermissions(cmd->subtype, rel, ATT_TABLE | ATT_MATVIEW); + + /* partitioned tables don't have an access method */ + if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE) + ereport(ERROR, + (errcode(ERRCODE_WRONG_OBJECT_TYPE), + errmsg("cannot change access method of a partitioned table"))); + + /* check if another access method change was already requested */ + if (OidIsValid(tab->newAccessMethod)) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("cannot have multiple SET ACCESS METHOD subcommands"))); + + ATPrepSetAccessMethod(tab, rel, cmd->name); + pass = AT_PASS_MISC; /* does not matter; no work in Phase 2 */ + break; case AT_SetTableSpace: /* SET TABLESPACE */ ATSimplePermissions(cmd->subtype, rel, ATT_TABLE | ATT_MATVIEW | ATT_INDEX | ATT_PARTITIONED_INDEX); @@ -4997,6 +5018,9 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab, case AT_DropOids: /* SET WITHOUT OIDS */ /* nothing to do here, oid columns don't exist anymore */ break; + case AT_SetAccessMethod: /* SET ACCESS METHOD */ + /* handled specially in Phase 3 */ + break; case AT_SetTableSpace: /* SET TABLESPACE */ /* @@ -5324,7 +5348,7 @@ ATRewriteTables(AlterTableStmt *parsetree, List **wqueue, LOCKMODE lockmode, /* * We only need to rewrite the table if at least one column needs to - * be recomputed, or we are changing its persistence. + * be recomputed, or we are changing its persistence or access method. * * There are two reasons for requiring a rewrite when changing * persistence: on one hand, we need to ensure that the buffers @@ -5338,6 +5362,7 @@ ATRewriteTables(AlterTableStmt *parsetree, List **wqueue, LOCKMODE lockmode, /* Build a temporary relation and copy data */ Relation OldHeap; Oid OIDNewHeap; + Oid NewAccessMethod; Oid NewTableSpace; char persistence; @@ -5379,6 +5404,15 @@ ATRewriteTables(AlterTableStmt *parsetree, List **wqueue, LOCKMODE lockmode, NewTableSpace = OldHeap->rd_rel->reltablespace; /* + * Select destination access method (same as original unless user + * requested a change) + */ + if (OidIsValid(tab->newAccessMethod)) + NewAccessMethod = tab->newAccessMethod; + else + NewAccessMethod = OldHeap->rd_rel->relam; + + /* * Select persistence of transient table (same as original unless * user requested a change) */ @@ -5417,8 +5451,8 @@ 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, NewAccessMethod, + persistence, lockmode); /* * Copy the heap data into the new table with the desired @@ -5933,6 +5967,8 @@ ATGetQueueEntry(List **wqueue, Relation rel) tab->rel = NULL; /* set later */ tab->relkind = rel->rd_rel->relkind; tab->oldDesc = CreateTupleDescCopyConstr(RelationGetDescr(rel)); + tab->newAccessMethod = InvalidOid; + tab->newTableSpace = InvalidOid; tab->newrelpersistence = RELPERSISTENCE_PERMANENT; tab->chgPersistence = false; @@ -6003,6 +6039,8 @@ alter_table_type_to_string(AlterTableType cmdtype) return "CLUSTER ON"; case AT_DropCluster: return "SET WITHOUT CLUSTER"; + case AT_SetAccessMethod: + return "SET ACCESS METHOD"; case AT_SetLogged: return "SET LOGGED"; case AT_SetUnLogged: @@ -13610,6 +13648,28 @@ ATExecDropCluster(Relation rel, LOCKMODE lockmode) } /* + * Preparation phase for SET ACCESS METHOD + * + * Check that access method exists. If it is the same as the table's current + * access method, it is 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 */ + tab->rewrite |= AT_REWRITE_ACCESS_METHOD; + tab->newAccessMethod = amoid; +} + +/* * ALTER TABLE SET TABLESPACE */ static void |