Adrian Klaver <adrian.klaver@xxxxxxxxxxx> writes: > On 11/16/2015 08:03 AM, Johannes wrote: >>> In every loop I execute an update with a where LIKE condition, which >>> relates to my current cursor position: >>> FOR i IN SELECT id, level_ids, path_names||'%' as path_names from x LOOP >>> update x set path_ids[i.level] = id where path_names like i.path_names; Probably the problem is that the planner is unable to fold i.path_names to a constant, so it can't derive an indexscan condition from the LIKE clause. A little bit of experimentation says that that will work if "i" is declared with a named rowtype, but not if it's declared RECORD. This might or might not be something we could fix, but in the meantime I'd try DECLARE i x%rowtype; FOR i IN SELECT * FROM x LOOP update x set path_ids[i.level] = id where path_names like (i.path_names || '%'); which while it might look less "constant" is actually more so from the planner's perspective, because there is no question of whether "i" has got a field of that name. regards, tom lane -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
