Downgrade to Percona 5.5

MySQL & MariaDB Other MySQL® Questions
1

Hi All,

I had to downgrade from Percona 5.6 back to 5.5 as I couldn’t get it to work with Cpanel (php wouldn’t compile and apache wouldn’t start with 5.6 installed). Running CentOS6.4 and Percona installed / upgraded via YUM.

Percona-Server-test-55-5.5.33-rel31.1.566.rhel6.x86_64
Percona-Server-devel-55-5.5.33-rel31.1.566.rhel6.x86_64
Percona-Server-server-55-5.5.33-rel31.1.566.rhel6.x86_64
Percona-Server-client-55-5.5.33-rel31.1.566.rhel6.x86_64
Percona-Server-shared-55-5.5.33-rel31.1.566.rhel6.x86_64
Percona-Server-shared-compat-5.5.33-rel31.1.566.rhel6.x86_64

Now, after downgrading, I’m getting a few errors relating to tables in the mysql database that were created during the upgrade process.

I’ve tried searching, and can’t find any information on this problem yet.

I managed to fix the issue with procs_priv.frm, general_log.frm and slow_log.frm by copying the .frm file over from another installation of 5.5, but I can’t seem to so anything with the other errors.

The only thing I’ve found relating to these tables is here : [URL]innodb - Cannot open table mysql/innodb_index_stats - Database Administrators Stack Exchange

Is it possible to drop those tables from the database if they aren’t needed in 5.5?

Thanks,
Matt

2

Hi,

I hope you know that while downgrade to 5.5, we need to check below things.
[URL]https://dev.mysql.com/doc/refman/5.6/en/downgrading.html[/URL]

Have you run mysql_upgrade after downgrade to 5.5? If not that I would suggest to do it and let us know if you still face the same issue.