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From:Tomislav Petrovic Date:April 23 1999 9:05am
Subject:Re: Question: how to count unique rows in multiple tables?
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Haven't checked this, so.........

SELECT COUNT(DISTINCT(master.id)) FROM master, a, b WHERE master.id=a.id OR
master.id=b.id;

Tomy.
-----Original Message-----
From: Kelly Yancey <kbyanc@stripped>
To: mysql@stripped <mysql@stripped>
Date: èetvrtak, travanj 22, 1999 17:23
Subject: Question: how to count unique rows in multiple tables?


>
>  I've run into a deceptively simple problem: I have 2 tables each which
>are associated with a 3rd table via an ID field, I need to count the
>number of rows with unique ID values in both of the 2 tables. For example:
>
>  Master Table
>  ID Name
>  --------------------------
>  0 Example
>  1 Another example
>  2 One more example
>  3 Final example
>
>  Table A
>  ID Data
>  -------------------------
>  0 Some associated data
>  0 Another piece of data
>  3 Yet more data
>
>  Table B
>  ID OtherData
>  ------------------------
>  0 Stuff
>  1 More Stuff
>  1 Even More Stuff
>
>  What I would be looking for is the number of rows with unique ID values
>between Table A and Table B (so the answer should be 3: (IDs 0, 1, and 3))
>How would I do this with a SQL query?
>
>  I really appreciate the help!
>
>  Kelly
>
> ~kbyanc@stripped~
> "Silly penguin, Linux is for kids"
>
>
>
>
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Thread
Question: how to count unique rows in multiple tables?Kelly Yancey22 Apr
Re: Question: how to count unique rows in multiple tables?Tomislav Petrovic23 Apr
  • Problem executing query, a bug perhaps?A. Brandic26 Apr
    • Re: Problem executing query, a bug perhaps?Jules Bean26 Apr
      • Re: Problem executing query, a bug perhaps?A. Brandic26 Apr
      • Re: Problem executing query, a bug perhaps?A. Brandic26 Apr
        • Re: Problem executing query, a bug perhaps?Jules Bean26 Apr
    • Re: Problem executing query, a bug perhaps?Sasha Pachev26 Apr