On Fri, Oct 29, 2004 at 05:13:02PM -0500, Jim C. Nasby wrote:
> Ok, next stupid question that I can't find in the docs... How would I
> join a table to an array? IE: if I have an array of primary keys for
> some table and I want to get the name field from that table and turn it
> back into an array, how would I do that?
See the "Subquery Expressions" and "Row and Array Comparisons"
sections in the PostgreSQL documentation:
http://www.postgresql.org/docs/7.4/static/functions-subquery.html
http://www.postgresql.org/docs/7.4/static/functions-comparisons.html
If I understand you correctly, this should work:
SELECT ARRAY(SELECT name FROM foo WHERE id = ANY(ARRAY[1,2,3]));
A test I just ran showed "id = ANY(ARRAY[1,2,3])" doing a sequential
scan whereas "id IN (1,2,3)" did an index scan, so you might want to
use the latter if possible.
--
Michael Fuhr
http://www.fuhr.org/~mfuhr/