On 16/03/10 13:05, Arnaud Lesauvage wrote:
Hi all ! PostgreSQL 8.4 here. I have a simple update query that looks like this : UPDATE t1 SET col = t2.col FROM t2 WHERE t1.key1 = t2.key1 AND t1.key2 = t2.key2; There is an index on (key1,key2) on the joined table (t2). This query does not use the index.
What does it do, then? The output of EXPLAIN would be a start if EXPLAIN ANALYSE is too expensive.
Oh - and how many rows will this actually update? -- Richard Huxton Archonet Ltd -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
