-----Original Message-----
From: Dmitry Teslenko [mailto:dteslenko@gmail.com]
Sent: Thursday, August 14, 2008 6:57 AM
To: pgsql-general@postgresql.org
Subject: Strange query plan
Hello!
I have following table:
CREATE TABLE table1 (
field1 INTEGER NOT NULL,
field2 INTEGER NOT NULL,
field3 CHARACTER(30),
... some more numeric fields)
I have also those indexes:
CREATE UNIQUE INDEX idx1 ON table1 USING btree (field3, field2, field1)
CREATE INDEX idx2 ON table1 USING btree (field1, field3)
Then I query this table with something like this:
SELECT SUM(...) FROM table1 WHERE field3 = 'ABC' AND field1 <> 1
GROUP BY field2
And planner picks up a sequential scan of a table. Why does he?
[I.N.]
How big is your table?
If it's not too big, the cost of table scan might be lower than using
index.
Igor