Re: MySQL auto_increment fields Server version: 5.1.32-community-log

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On Sun, 9 Aug 2009 20:17:15 +0200, "Ralph Deffke" wrote:

> I'm facing the fact that it seems that auto_increment fields in a table not
> start at 1 like it was in earlier versions even if I install mySQL brand new
> creating all tables new. it seems to me that auto_increments handling has
> changed to older version. is somebody out there who can give me a quick
> background about auto_increment and how and if I can control the behavior of
> mySQL about them.

Did you Google for it? I found the following page that
might be relevant:

<http://dev.mysql.com/doc/refman/5.1/en/innodb-auto-increment-handling.html>

   "Beginning with MySQL 5.1.22, InnoDB provides a locking
    strategy that significantly improves scalability and
    performance of SQL statements that add rows to tables
    with AUTO_INCREMENT columns.
    ...
    InnoDB uses the following algorithm to initialize the
    auto-increment counter for a table t that contains an
    AUTO_INCREMENT column named ai_col: After a server
    startup, for the first insert into a table t, InnoDB
    executes the equivalent of this statement: 

      SELECT MAX(ai_col) FROM t FOR UPDATE;

    InnoDB increments by one the value retrieved by the
    statement and assigns it to the column and to the
    auto-increment counter for the table."


/Nisse

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