>>>>> "Andrew" == Andrew Gierth <andrew@tao11.riddles.org.uk> writes:
Andrew> Bingo - I have a test case, which I'll post in a sec after
Andrew> testing it on other versions.
OK, not only does it break in latest 9.3 stable, it also breaks in
current master.
This is the testcase:
create table mytable (id integer, foo text[] default '{}', flag boolean default false);
insert into mytable select generate_series(1,10);
now in session B do:
begin; update mytable set foo='{baz}', flag=true where id=6;
-- leave transaction open
and in session A:
with tmp(f2) as (select array['foo'])
update mytable set foo = case when not flag then foo
when foo @> (select f2 from tmp) then foo
else foo || (select f2 from tmp) end
where id=6;
-- hangs on row lock
Then commit in session B, and watch A go down in flames.
Going to see if this can be narrowed down further.
--
Andrew (irc:RhodiumToad)