Stephen Frost <sfrost@xxxxxxxxxxx> wrote: >> > Just thinking about it now; do SQL's semantics say it'll always do >> > the right thing? PG does in a couple of quick tests (i.e. one where >> > customer is a small table and PG prefers a seqscan and where it's larger >> > and prefers an index scan) but I'm not sure if this could change. >> PostgreSQL's documentation on VALUES has at least no guaran- >> tee of the order of data. I'd prefer David's solution :-). > Uhm, that's why there's an explicit ORDER BY.. I seriously doubt that > would ever be violated. If there was an approach suggested which didn't > include an ORDER BY *somewhere*, I'd be suspect of it. The query read: | SELECT c.* | FROM customer c, ( | SELECT *, row_number() OVER () | FROM (VALUES (23), (56), (2), (12), (10)) x) x(val,ord) | WHERE c.id = x.val | ORDER BY x.ord; and the question is whether "VALUES (1), (2), (3)" will al- ways return "(1)", "then" "(2)", "then" "(3)" and whether "ROW_NUMBER() OVER ()" will always keep that order intact. Tim -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
