I recently helped a customer figure out why a minor version MySQL upgrade was indicating that some tables needed to be rebuilt. The mysql_upgrade program should be run for every upgrade, no matter how big or small the version difference is, but when only the minor version changes, I would normally not expect it to require tables to be rebuilt.
Turns out some of their tables were still marked with an older MySQL version, which could mean a few things… most likely that something went wrong with a previous upgrade, or that the tables were copied from a server with an older version.
In cases like this, did you know there is a fast, safe and simple way to check the version associated with a table? You can do this by reading the FRM file, following the format specification found here.
If you look at that page, you’ll see that the …[Read more]