← Back to team overview

maria-developers team mailing list archive

Empty directory in mariadb's datadir is not handled correctly


Hi guys,

quite tricky problem came up after a directory has been created by something else than mysqld in the datadir.

Suppose we use datadir=/var/lib/mysql. When we create any file in that directory by hand (or some program does it, which is not just imagination, it really happens), e.g. /var/lib/mysql/.local, MariaDB (Oracle's MySQL will behave the same probably) server thinks this directory is a database, which is wrong.

Then we get some weird messages and outputs:

# mysqlshow
|     Databases      |
| information_schema |
| #mysql50#.local    |
| mysql              |
| performance_schema |
| test               |

# mysqlcheck -A
mysqlcheck: Got error: 1102: Incorrect database name '#mysql50#.local' when selecting the database

I believe this is not how the things should work. I'm not sure, but I'd expect there is still some information about existing databases in the information_schema table. So IMHO the server/tool should always fetch such info in addition to pure testing if the database directory exists. Or is such testing simply impossible?


Follow ups