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From:Chris W Date:November 25 2007 8:46pm
Subject:Re: Incrementing a "Private" Integer Space
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David T. Ashley wrote:
> Hi Chris,
>
> OK, I will try that.  Thanks for the help.
>
> My assumption in reading your original post was that you didn't understand
> what I wanted to do (but you did).
>
> In order for me to use the solution you have proposed, in addition to
> working, this behavior would have to be described in the MySQL manual.  The
> reason is that this seems to be the kind of behavior that could change from
> version to version.
>
> <BEGIN IMPORTANT POINT>
> I don't suppose you know the section in the manual that defines the behavior
> you're describing?
> <END IMPORTANT POINT>
>   
 From '3.6.9. Using AUTO_INCREMENT'

"For MyISAM and BDB tables you can specify AUTO_INCREMENT on a secondary 
column in a multiplecolumn
index. In this case, the generated value for the AUTO_INCREMENT column 
is calculated as
MAX(auto_increment_column) + 1 WHERE prefix=given-prefix. This is useful 
when
you want to put data into ordered groups."

I didn't know it only worked in MyISAM and BDB... I almost always use 
MyISAM anyway.  However I don't use that feature anymore due to my 
change in thinking on primary keys.   The only time I use a primary key 
that has more than one field is if the table is a "many to many 
relationship" table and in that case neither field is auto increment.



-- 
Chris W
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Thread
Incrementing a "Private" Integer SpaceDavid T. Ashley25 Nov
  • Re: Incrementing a "Private" Integer SpaceChris W25 Nov
  • Re: Incrementing a "Private" Integer SpaceStut25 Nov
    • Re: Incrementing a "Private" Integer SpaceDavid T. Ashley25 Nov
      • Re: Incrementing a "Private" Integer SpaceStut25 Nov
    • Re: Incrementing a "Private" Integer SpaceChris W25 Nov
      • Re: Incrementing a "Private" Integer SpaceDavid T. Ashley25 Nov
        • Re: Incrementing a "Private" Integer SpaceChris W25 Nov
        • RE: Incrementing a "Private" Integer SpaceMartin Gainty25 Nov
          • Re: Incrementing a "Private" Integer SpaceDavid T. Ashley25 Nov