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Re: Row size too large


Am 20.01.2015 um 20:53 schrieb Jeremy Cole:
Since I was the author of the bug this addressed, MySQL Bug 69477
<http://bugs.mysql.com/bug.php?id=69477> I could comment here.

The InnoDB redo log (innodb_log_file_size) needs to be at least 10x
larger than the largest single BLOB value you intend to store, not
larger than the sum of BLOB data. If you are seeing this error with a
log file size of 128 MB, that implies that you have some BLOB column
containing at least 12.8 MB. Is that the case? Your use is probably
quite strange if your total data size is only 129 MB and you have BLOBs
of that size, but be aware: this bug fix was for a very serious bug.
With the previous behavior usage of such large BLOBs could result in
silent and unrecoverable data loss after a crash due to overwriting the
most recent checkpoint with oversized BLOB data.

this is a tiny dbmail-testserver

there are a few testmessages, the largest one is 8.0 MB
on the other hand we support up to 35 MB mail size

the whole "dbmail_mimeparts" is around 90 MB

so *no*, i don't get any reason why i need > 128 MB "innodb_log_file_size" for a "optimize table" AKA re-create

no idea what that possibly implies on a server storing larger files for attachments in a web-app to "passthru" them with a PHP application because the current error leads to make "innodb_log_file_size" very large and clearly waste storage on a virtualized environment ending innodb logs larger then the whole dataset

what i *really* hate in that behavior change is that you can't happily change that config var at all on a production server and the idea to increase it for safety to huge values larger then the data itself

My understanding is that the bug was addressed in 5.7 without
introducing a limitation.

On Tue, Jan 20, 2015 at 1:22 AM, Reindl Harald wrote:

    WTF: "the innodb_log_file_size setting should be 10 times larger
    than the largest BLOB data size found in the rows of your tables" -
    how is that maintainable for a sysadmin?

    the whole (file_per_table) database folder is 129 MB,
    innodb_log_file_size is 128 MB and nobody can seriously explain me
    that i need a innodb_log_file_size with magnitudes of the whole datasize

    Am 20.01.2015 um 03:04 schrieb Jean Weisbuch:

        It seems that the limitation has been introduced on MySQL 5.6.20 :

        Le 20/01/2015 01:03, Reindl Harald a écrit :

            InnoDB: The total blob data length (13476124) is greater
            than 10% of
            the redo log file size (5120). Please increase

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