Function ATExecSetTableSpace

src/backend/commands/tablecmds.c:16392–16529

* Execute ALTER TABLE SET TABLESPACE for cases where there is no tuple * rewriting to be done, so we just want to copy the data as fast as possible. */

 * rewriting to be done, so we just want to copy the data as fast as possible.
 */
static void
ATExecSetTableSpace(Oid tableOid, Oid newTableSpace, LOCKMODE lockmode)
{
	Relation	rel;
	Oid			reltoastrelid;
	Oid			relaosegrelid = InvalidOid;
	Oid			relaoblkdirrelid = InvalidOid;
	Oid			relaoblkdiridxid = InvalidOid;
	Oid         relaovisimaprelid = InvalidOid;
	Oid         relaovisimapidxid = InvalidOid;
	Oid			relbmrelid = InvalidOid;
	Oid			relbmidxid = InvalidOid;
	Oid newrelfilenode;
	RelFileNode newrnode;
	List	   *reltoastidxids = NIL;
	ListCell   *lc;

	/*
	 * Need lock here in case we are recursing to toast table or index
	 */
	rel = relation_open(tableOid, lockmode);

	/* Check first if relation can be moved to new tablespace */
	if (!CheckRelationTableSpaceMove(rel, newTableSpace))
	{
		InvokeObjectPostAlterHook(RelationRelationId,
								  RelationGetRelid(rel), 0);
		relation_close(rel, NoLock);
		return;
	}

	reltoastrelid = rel->rd_rel->reltoastrelid;
	/* Fetch the list of indexes on toast relation if necessary */
	if (OidIsValid(reltoastrelid))
	{
		Relation	toastRel = relation_open(reltoastrelid, lockmode);

		reltoastidxids = RelationGetIndexList(toastRel);
		relation_close(toastRel, lockmode);
	}

	/* Get the ao sub objects */
	if (RelationStorageIsAO(rel))
		GetAppendOnlyEntryAuxOids(rel,
								  &relaosegrelid,
								  &relaoblkdirrelid, &relaoblkdiridxid,
								  &relaovisimaprelid, &relaovisimapidxid);

	/* Get the bitmap sub objects */
	if (RelationIsBitmapIndex(rel))
		GetBitmapIndexAuxOids(rel, &relbmrelid, &relbmidxid);

	/*
	 * Relfilenodes are not unique in databases across tablespaces, so we need
	 * to allocate a new one in the new tablespace.
	 */
	newrelfilenode = GetNewRelFileNode(newTableSpace, NULL,
									   rel->rd_rel->relpersistence);