Re: Disable cross products in postgres

From: Gourav Kumar <gourav1905(at)gmail(dot)com>
To: fabriziomello(at)gmail(dot)com
Cc: Robert Haas <robertmhaas(at)gmail(dot)com>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: Disable cross products in postgres
Date: 2017-10-13 20:50:01
Message-ID: CAPzqDmjm+j1keZHOjsQv4GieNw8VrWogkKbpiB8SH6=pJYGHmQ@mail.gmail.com
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I tried debugging the code, at no point in execution the function
make_rels_by_clauseless_joins
was called. Although optimizer did consider some of the joins which are
cross products.

On 14 October 2017 at 01:57, Gourav Kumar <gourav1905(at)gmail(dot)com> wrote:

> Can I use something like joininfo, which will store the join predicates
> and I can check if there is no join predicate among the two relations don't
> consider them.
>
> On 14 October 2017 at 01:48, Fabrízio de Royes Mello <
> fabriziomello(at)gmail(dot)com> wrote:
>
>>
>> On Fri, Oct 13, 2017 at 5:08 PM, Robert Haas <robertmhaas(at)gmail(dot)com>
>> wrote:
>> >
>> > On Fri, Oct 13, 2017 at 4:06 PM, Gourav Kumar <gourav1905(at)gmail(dot)com>
>> wrote:
>> > > Can you guide me where to look for it?
>> >
>> > Search for make_rels_by_clauseless_joins.
>> >
>>
>> I wonder if it's possible implement it as an extension using some hook
>>
>> --
>> Fabrízio de Royes Mello
>> Consultoria/Coaching PostgreSQL
>> >> Timbira: http://www.timbira.com.br
>> >> Blog: http://fabriziomello.github.io
>> >> Linkedin: http://br.linkedin.com/in/fabriziomello
>> >> Twitter: http://twitter.com/fabriziomello
>> >> Github: http://github.com/fabriziomello
>>
>
>
>
> --
> Thanks,
> Gourav Kumar
> Computer Science and Automation
> Indian Institute of Science
>

--
Thanks,
Gourav Kumar
Computer Science and Automation
Indian Institute of Science

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