Обсуждение: pgsql: Fix another join removal bug: the check on PlaceHolderVars was w
Fix another join removal bug: the check on PlaceHolderVars was wrong. The previous coding would decide that join removal was unsafe upon finding a PlaceHolderVar that needed to be evaluated at the inner rel and then used above the join. However, this fails to cover the case of PlaceHolderVars that refer to both the inner rel and some other rels. Per bug report from Andrus. Branch ------ REL9_0_STABLE Details ------- http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=7fc8db849106db91e1053ed25045eb4fa877f212 Modified Files -------------- src/backend/optimizer/plan/analyzejoins.c | 18 +++++++++++++----- src/test/regress/expected/join.out | 21 +++++++++++++++++++++ src/test/regress/sql/join.sql | 15 +++++++++++++++ 3 files changed, 49 insertions(+), 5 deletions(-)
On Sat, Sep 25, 2010 at 11:04:28PM +0000, Tom Lane wrote: > Fix another join removal bug: the check on PlaceHolderVars was > wrong. > > The previous coding would decide that join removal was unsafe upon > finding a PlaceHolderVar that needed to be evaluated at the inner > rel and then used above the join. However, this fails to cover the > case of PlaceHolderVars that refer to both the inner rel and some > other rels. Per bug report from Andrus. The person who found it originally was Kirill (xitology) Simonov. He brought it up in IRC. :) Cheers, David. -- David Fetter <david@fetter.org> http://fetter.org/ Phone: +1 415 235 3778 AIM: dfetter666 Yahoo!: dfetter Skype: davidfetter XMPP: david.fetter@gmail.com iCal: webcal://www.tripit.com/feed/ical/people/david74/tripit.ics Remember to vote! Consider donating to Postgres: http://www.postgresql.org/about/donate
David Fetter <david@fetter.org> writes:
> On Sat, Sep 25, 2010 at 11:04:28PM +0000, Tom Lane wrote:
>> The previous coding would decide that join removal was unsafe upon
>> finding a PlaceHolderVar that needed to be evaluated at the inner
>> rel and then used above the join. However, this fails to cover the
>> case of PlaceHolderVars that refer to both the inner rel and some
>> other rels. Per bug report from Andrus.
> The person who found it originally was Kirill (xitology) Simonov. He
> brought it up in IRC. :)
[ shrug ... ] I can only go by what I see in the bug report.
regards, tom lane
On Sunday 26 September 2010 02:29:16 David Fetter wrote: > On Sat, Sep 25, 2010 at 11:04:28PM +0000, Tom Lane wrote: > > Fix another join removal bug: the check on PlaceHolderVars was > > wrong. > > > > The previous coding would decide that join removal was unsafe upon > > finding a PlaceHolderVar that needed to be evaluated at the inner > > rel and then used above the join. However, this fails to cover the > > case of PlaceHolderVars that refer to both the inner rel and some > > other rels. Per bug report from Andrus. > > The person who found it originally was Kirill (xitology) Simonov. He > brought it up in IRC. :) No, thats a different bug... For one its affecting 8.4 at least as well, for another its not yet fixed ;-) Andres