At 11:13 AM 25/04/2003 -0400, Tom Lane wrote:
>The point is that the system *may* choose to evaluate f() only once,
>not that it *must* do so. The classification exists to make it valid
>to use an indexscan on "col".
So just for my own understanding, the optimizer does not know that it can
treat a STABLE function f as constant inside an outer loop of t1 in this query:
select * from t1,t2 where t2.f1 = f(t1.f1)
----------------------------------------------------------------
Philip Warner | __---_____
Albatross Consulting Pty. Ltd. |----/ - \
(A.B.N. 75 008 659 498) | /(@) ______---_
Tel: (+61) 0500 83 82 81 | _________ \
Fax: (+61) 03 5330 3172 | ___________ |
Http://www.rhyme.com.au | / \| | --________--
PGP key available upon request, | /
and from pgp5.ai.mit.edu:11371 |/