6.99. setaddsequence_int(integer, integer, text, text)

Function Properties

Language: PLPGSQL

Return Type: integer

setAddSequence_int (set_id, seq_id, seq_fqname, seq_comment) This processes the SET_ADD_SEQUENCE event. On remote nodes that subscribe to set_id, add the sequence to the replication set.

declare
	p_set_id			alias for $1;
	p_seq_id			alias for $2;
	p_fqname			alias for $3;
	p_seq_comment		alias for $4;
	v_local_node_id		int4;
	v_set_origin		int4;
	v_sub_provider		int4;
	v_relkind			char;
	v_seq_reloid		oid;
	v_seq_relname		name;
	v_seq_nspname		name;
	v_sync_row			record;
begin
	-- ----
	-- Grab the central configuration lock
	-- ----
	lock table sl_config_lock;

	-- ----
	-- 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 = p_set_id;
	if not found then
		raise exception 'Slony-I: setAddSequence_int(): set % not found',
				p_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 = p_set_id
				and sub_receiver = getLocalNodeId('_schemadoc');
		if not found then
			return 0;
		end if;
	end if;
	
	-- ----
	-- Get the sequences OID and check that it is a sequence
	-- ----
	select PGC.oid, PGC.relkind, PGC.relname, PGN.nspname 
		into v_seq_reloid, v_relkind, v_seq_relname, v_seq_nspname
			from "pg_catalog".pg_class PGC, "pg_catalog".pg_namespace PGN
			where PGC.relnamespace = PGN.oid
			and slon_quote_input(p_fqname) = slon_quote_brute(PGN.nspname) ||
					'.' || slon_quote_brute(PGC.relname);
	if not found then
		raise exception 'Slony-I: setAddSequence_int(): sequence % not found', 
				p_fqname;
	end if;
	if v_relkind != 'S' then
		raise exception 'Slony-I: setAddSequence_int(): % is not a sequence',
				p_fqname;
	end if;

        select 1 into v_sync_row from sl_sequence where seq_id = p_seq_id;
	if not found then
               v_relkind := 'o';   -- all is OK
        else
                raise exception 'Slony-I: setAddSequence_int(): sequence ID % has already been assigned', p_seq_id;
        end if;

	-- ----
	-- Add the sequence to sl_sequence
	-- ----
	insert into sl_sequence
		(seq_id, seq_reloid, seq_relname, seq_nspname, seq_set, seq_comment) 
		values
		(p_seq_id, v_seq_reloid, v_seq_relname, v_seq_nspname,  p_set_id, p_seq_comment);

	-- ----
	-- On the set origin, fake a sl_seqlog row for the last sync event
	-- ----
	if v_set_origin = v_local_node_id then
		for v_sync_row in select coalesce (max(ev_seqno), 0) as ev_seqno
				from sl_event
				where ev_origin = v_local_node_id
					and ev_type = 'SYNC'
		loop
			insert into sl_seqlog
					(seql_seqid, seql_origin, seql_ev_seqno, 
					seql_last_value) values
					(p_seq_id, v_local_node_id, v_sync_row.ev_seqno,
					sequenceLastValue(p_fqname));
		end loop;
	end if;

	return p_seq_id;
end;