Re: [HACKERS] Sort of a planner regression 8.3-8.4 (due to EXISTS inlining) and related stuff

2010-05-16 Thread Andres Freund
Testschema: ROLLBACK; BEGIN; CREATE TABLE a ( a_id serial PRIMARY KEY NOT NULL, b_id integer ); CREATE INDEX a__b_id ON a USING btree (b_id); CREATE TABLE b ( b_id serial NOT NULL, c_id integer ); CREATE INDEX b__c_id ON b USING btree (c_id); CREATE TABLE c ( c_id serial

Re: [HACKERS] Sort of a planner regression 8.3-8.4 (due to EXISTS inlining) and related stuff

2010-05-16 Thread Robert Haas
On Sun, May 16, 2010 at 7:07 PM, Andres Freund and...@anarazel.de wrote: Reducing the (large and ugly, automatically generated queries) to a reproducible testcase I ended up with the following pattern: explain SELECT 1 FROM    c WHERE    EXISTS (        SELECT *        FROM a            

Re: [HACKERS] Sort of a planner regression 8.3-8.4 (due to EXISTS inlining) and related stuff

2010-05-16 Thread Tom Lane
Robert Haas robertmh...@gmail.com writes: I believe this is a result of a limitation we've discussed previously, namely, that the planner presently uses a limited, special-case kludge to consider partial index scans, and the executor uses another kludge to execute them. Yeah. To restore

Re: [HACKERS] Sort of a planner regression 8.3-8.4 (due to EXISTS inlining) and related stuff

2010-05-16 Thread Andres Freund
On Monday 17 May 2010 04:10:46 Tom Lane wrote: Robert Haas robertmh...@gmail.com writes: I believe this is a result of a limitation we've discussed previously, namely, that the planner presently uses a limited, special-case kludge to consider partial index scans, and the executor uses