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From:Benjamin Stillman Date:February 26 2013 7:04pm
Subject:RE: data loss due to misconfiguration
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Are you actually querying the table (select count(*) from table_name), or just the stats
(show table status)? Is the table Innodb?

If  you're using Innodb and aren't doing a select count (or other select query) on the
table, then yes you'll have varying results. This is because unlike MyISAM, Innodb does
not keep a count of the records. Using show table status gives just an estimation. This
would be my first path of investigation.

http://dev.mysql.com/doc/refman/5.5/en/show-table-status.html

"The number of rows. Some storage engines, such as MyISAM, store the exact count. For
other storage engines, such as InnoDB, this value is an approximation, and may vary from
the actual value by as much as 40 to 50%. In such cases, use SELECT COUNT(*) to obtain an
accurate count."



-----Original Message-----
From: Zachary Stern [mailto:zs@stripped]
Sent: Tuesday, February 26, 2013 12:42 PM
To: mysql@stripped
Subject: data loss due to misconfiguration

Is such a thing possible? There are no errors or issues, but we can query a table, get X
number of rows, query it later, and all of the sudden be missing a thousand rows.

I know this isn't much to go on, but I'm not even sure what information to provide. Will
be happy to give anything you guys might be able to think of.

TIA.

-Zachary

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Thread
data loss due to misconfigurationZachary Stern26 Feb
  • RE: data loss due to misconfigurationBenjamin Stillman26 Feb
    • RE: data loss due to misconfigurationRick James26 Feb
      • Re: data loss due to misconfigurationZachary Stern26 Feb
        • Re: data loss due to misconfigurationReindl Harald26 Feb
          • Re: data loss due to misconfigurationZachary Stern26 Feb
            • Re: data loss due to misconfigurationshawn green26 Feb
              • RE: data loss due to misconfigurationBenjamin Stillman26 Feb