Re: bug or lacking doc hint
От
Ron
Тема
Re: bug or lacking doc hint
Дата
Msg-id
20ce23c6-3c35-e5ce-b5bd-edb3371786a2@gmail.com
Ответ на
bug or lacking doc hint (Marc Millas)
Список
Дерево обсуждения
bug or lacking doc hint Marc Millas <marc.millas@mokadb.com>
Re: bug or lacking doc hint Ron <ronljohnsonjr@gmail.com>
Re: bug or lacking doc hint David Rowley <dgrowleyml@gmail.com>
Re: bug or lacking doc hint Tom Lane <tgl@sss.pgh.pa.us>
Re: bug or lacking doc hint Marc Millas <marc.millas@mokadb.com>
Re: bug or lacking doc hint Avin Kavish <avin@baseboard.ai>
Re: bug or lacking doc hint Marc Millas <marc.millas@mokadb.com>
Re: bug or lacking doc hint Ron <ronljohnsonjr@gmail.com>
Re: bug or lacking doc hint Marc Millas <marc.millas@mokadb.com>
Re: bug or lacking doc hint Kirk Wolak <wolakk@gmail.com>
regex failing Zahir Lalani <ZahirLalani@oliver.agency>
Re: regex failing Sergey Fukanchik <fukanchik@gmail.com>
RE: regex failing Zahir Lalani <ZahirLalani@oliver.agency>
Re: regex failing Steve Baldwin <steve.baldwin@gmail.com>
Re: regex failing "David G. Johnston" <david.g.johnston@gmail.com>
Re: bug or lacking doc hint Marc Millas <marc.millas@mokadb.com>
On 6/25/23 10:01, Marc Millas wrote: > Hi, > > I have had a perf (++) pb with a join plan cf the pb with join plan thread. > I did simplify the thing up to when its a simple join between a 15M lines > table and a 30k lines table. > if I put in the on part something like table1.a=table2.b, Postgres does > the job in around 1 seconde. > > if in the on part of the join I write table1.a=table2.b OR > substr(table1.c,x,x) =table2.d That left side SUBSTR() can't be good for the query optimizer. (Or I'm old and still using habits picked up 25 years ago on a different RDBMS.) Maybe a function index on table1 would help. -- Born in Arizona, moved to Babylonia.
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