6.103. setdropsequence_int(integer)

Function Properties

Language: PLPGSQL

Return Type: integer

setDropSequence_int (seq_id) This processes the SET_DROP_SEQUENCE event. On remote nodes that subscribe to the set containing sequence seq_id, drop the sequence from the replication set.

declare
	p_seq_id		alias for $1;
	v_set_id		int4;
	v_local_node_id		int4;
	v_set_origin		int4;
	v_sub_provider		int4;
	v_relkind			char;
	v_sync_row			record;
begin
	-- ----
	-- Grab the central configuration lock
	-- ----
	lock table sl_config_lock;

	-- ----
	-- Determine set id for this sequence
	-- ----
	select seq_set into v_set_id from sl_sequence where seq_id = p_seq_id;

	-- ----
	-- Ensure sequence exists
	-- ----
	if not found then
		return 0;
	end if;

	-- ----
	-- For sets with a remote origin, check that we are subscribed 
	-- to that set. Otherwise we ignore the sequence because it might 
	-- not even exist in our database.
	-- ----
	v_local_node_id := getLocalNodeId('_schemadoc');
	select set_origin into v_set_origin
			from sl_set
			where set_id = v_set_id;
	if not found then
		raise exception 'Slony-I: setDropSequence_int(): set % not found',
				v_set_id;
	end if;
	if v_set_origin != v_local_node_id then
		select sub_provider into v_sub_provider
				from sl_subscribe
				where sub_set = v_set_id
				and sub_receiver = getLocalNodeId('_schemadoc');
		if not found then
			return 0;
		end if;
	end if;

	-- ----
	-- drop the sequence from sl_sequence, sl_seqlog
	-- ----
	delete from sl_seqlog where seql_seqid = p_seq_id;
	delete from sl_sequence where seq_id = p_seq_id;

	return p_seq_id;
end;