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From:Hector Del Curto Date:October 22 2003 5:25pm
Subject:2 Query with same criteria giving different number of rows
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I have this 2 queries:

SELECT COUNT(DISTINCT(LEFT(p.prod_num,5))) FROM products p, tlines l,
prod_line pl WHERE l.Line = 'Solaris' AND l.id=pl.line_id AND pl.prod_id =
p.id_product

SELECT DISTINCT(LEFT(p.prod_num,5))as prod_num, p.description AS
description,l.Line as line,l.Content as content FROM products p, tlines l,
prod_line pl WHERE l.Line = 'Solaris' AND l.id=pl.line_id AND pl.prod_id =
p.id_product

The only difference between them is that in one I want the count of rows and
on the other I want the columns.
When I run the queries I get for example 24 as result of the count and on
the other query I get 26 records.
In those 26 records I get 2 prod_num duplicated when I'm asking for
DISTINCT.
Now, the other thing is if I only leave the prod_num column the number of
rows are the same, if I add another column it changes to 26.
I know I have some duplicates on the second table, and that's affecting the
results, but I don't know why.
Any hint on why is that happening?



													Thanks,
														Hector

Thread
MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Heikki Tuuri22 Oct
  • Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Chris Nolan22 Oct
  • 2 Query with same criteria giving different number of rowsHector Del Curto22 Oct
    • Re: 2 Query with same criteria giving different number of rowsChris Tucker22 Oct
    • Re: 2 Query with same criteria giving different number of rowsIllyes Laszlo23 Oct
  • Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Eduardo D Piovesam23 Oct
  • Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Eduardo D Piovesam23 Oct
Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Heikki Tuuri24 Oct
Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Heikki Tuuri24 Oct
  • Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Martijn Tonies24 Oct
    • Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Chris Nolan24 Oct
  • Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Eduardo D Piovesam24 Oct
    • MySQL/InnoDB-4.0.16 +Optimizer behaviourSergey S. Kostyliov29 Oct
  • Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Heikki Tuuri24 Oct
  • Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Eduardo D Piovesam24 Oct
  • Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Martijn Tonies24 Oct
  • Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Heikki Tuuri27 Oct
Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Heikki Tuuri26 Oct
Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Martijn Tonies26 Oct
Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Jon Hancock27 Oct
  • Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1Chris Nolan27 Oct
    • InnoDB on Raw partitions in OSX (was Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1)Gabriel Ricard27 Oct
  • Partial replicate InnoDB -> MyISAMJon Hancock28 Oct
    • Re: Partial replicate InnoDB -> MyISAMChris Nolan28 Oct
  • Re: Partial replicate InnoDB -> MyISAMJon Hancock28 Oct
Re: InnoDB on Raw partitions in OSX (was Re: MySQL/InnoDB-4.0.16 is released + sneak peek of 4.1.1)Heikki Tuuri27 Oct