I have the following 2 functions and I’m getting deadlocks when I call them from multiple threads. The first, I’m not sure why because I’m doing a select for update. The second I’m doing an insert on, and I thought insert will automatically do a lock as it inserts:
-------------FUNCTION 1: -------------
CREATE OR REPLACE FUNCTION public.select_pend_visitation_for_unvisited_links(int4)
RETURNS SETOF record AS
'
DECLARE
urlrow RECORD;
BEGIN
FOR urlrow in EXECUTE \'SELECT * FROM "URL" WHERE visited=1::int2 LIMIT \' || $1::int4 || \'FOR UPDATE\'
LOOP
UPDATE "URL" SET visited=2 WHERE "URLID"::int8 = urlrow."URLID"::int8;
RETURN NEXT urlrow;
END LOOP;
RETURN;
END;
'
LANGUAGE 'plpgsql' VOLATILE;
-------------FUNCTION 2: -------------
CREATE OR REPLACE FUNCTION public.add_link_to_url_table(varchar, int8, int4, int2, bool, int2)
RETURNS void AS
'
INSERT INTO "URL"
("rootlessURLString","rootURLID","rootURLIDPartition","visited",
"createdAt","updatedAt","isValid","URLType")
VALUES ($1, $2, $3, $4, now(), now(), $5, $6 );
'
LANGUAGE 'sql' VOLATILE;
Thanx for the help,
amir