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From:Sergei Golubchik Date:May 25 2009 10:16am
Subject:Re: GSoC Week 3 - I_S/P_S storage engine
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Hi, Arjen!

On May 25, Arjen Lentz wrote:
> I mean, if I do a query about 1 table on an information schema table,
> then mysqld will first run through all tables in all databases,
> prouduce the temporary table of everything (most likely on disk), and
> then run my query on it.

Depends on the query. If you do a query about 1 table on an information
schema table, like, for example, SELECT ... FROM I_S.TABLES WHERE
SCHEMA_NAME='d1' AND TABLE_NAME='t1' - MySQL will not run through all
tables in all databases. It'll open d1/t1.frm directly. Or may not do
even that, for example for SELECT TABLE_NAME FROM ... - it doesn't need
to open frm, it's enough to verify that the frm file exists.

> Please see this as a vote of encouragement for the project.  I
> sincerely hope that an I_S engine will deal (more) sensibly with these
> issues.

more sensibly - yes, but it won't do wonders. Metadata will still be in
frm files.

Regards / Mit vielen Grüßen,
Sergei

-- 
   __  ___     ___ ____  __
  /  |/  /_ __/ __/ __ \/ /   Sergei Golubchik <serg@stripped>
 / /|_/ / // /\ \/ /_/ / /__  Principal Software Engineer/Server Architect
/_/  /_/\_, /___/\___\_\___/  Sun Microsystems GmbH, HRB München 161028
       <___/                  Sonnenallee 1, 85551 Kirchheim-Heimstetten
Geschäftsführer: Thomas Schroeder, Wolfgang Engels, Wolf Frenkel
Vorsitzender des Aufsichtsrates: Martin Häring
Thread
GSoC Week 3 - I_S/P_S storage enginescut_tang25 May
  • Re: GSoC Week 3 - I_S/P_S storage engineSergei Golubchik25 May
    • Re: GSoC Week 3 - I_S/P_S storage engineArjen Lentz25 May
      • Re: GSoC Week 3 - I_S/P_S storage engineSergei Golubchik25 May
        • Re: GSoC Week 3 - I_S/P_S storage engineArjen Lentz25 May
          • Re: GSoC Week 3 - I_S/P_S storage engineSergei Golubchik25 May
            • Re: GSoC Week 3 - I_S/P_S storage engineArjen Lentz25 May