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From:Paul DuBois Date:October 3 2000 5:06pm
Subject:Re: MySQL 3.23.25 released
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At 4:56 PM +0200 10-03-2000, Carsten Gehling wrote:
>From: "Benjamin Pflugmann" <philemon@stripped>
>Sent: Tuesday, October 03, 2000 4:45 PM
>
>>  Maybe I completely misunderstand you, but what is wrong with the plain
>>  JOIN?
>>
>>  SELECT * FROM table1, table2 WHERE table1.id = table2.id
>>
>>  results in exactly what you ask for, doesn't it?
>
>Yes, but the performance is poor. The above statement makes a cartesian
>product, where every record in table1 is combined with every record in
>table2. Only after this cartesian product is completed, are the correct
>records selected and returned.

What is your basis for saying that?  MySQL doesn't do any such thing.
If performance is poor, do you have indexes on the id columns in each
table?

-- 
Paul DuBois, paul@stripped
Thread
MySQL 3.23.25 releasedMichael Widenius28 Sep
  • RE: MySQL 3.23.25 releasedSander Pilon28 Sep
    • RE: MySQL 3.23.25 releasedMichael Widenius29 Sep
      • RE: MySQL 3.23.25 releasedSander Pilon29 Sep
  • Re: MySQL 3.23.25 releasedCarsten Gehling3 Oct
    • Re: MySQL 3.23.25 releasedBenjamin Pflugmann3 Oct
      • Re: MySQL 3.23.25 releasedMichael Widenius4 Oct
  • Re: MySQL 3.23.25 releasedArtem Koutchine3 Oct
  • Re: MySQL 3.23.25 releasedCarsten Gehling3 Oct
    • Re: MySQL 3.23.25 releasedDan Nelson3 Oct
    • Re: MySQL 3.23.25 releasedPaul DuBois3 Oct
    • Re: MySQL 3.23.25 releasedBenjamin Pflugmann3 Oct
  • Re: MySQL 3.23.25 releasedCarsten Gehling4 Oct
  • Re: MySQL 3.23.25 releasedCarsten Gehling4 Oct