BASH Quickie: Backing Up MySQL Databases

In some ways, after years of doing programming and scripting, I’m now sort of rediscovering the power of the shell.

Tonight, I was working on my server and remembered that I needed to start backing up my MySQL databases (which you do also … right?). So instead of writing a script to do that, with a little research, I was able to come up with a way to:

  1. Dump each database to a separate SQL file, with a timestamp.

  2. bzip the file.

  3. Keep 5 days worth of backups for each database, rotating the oldest backup off.

Here’s what I came up with:

cd /backup/mysql;
for i in $(mysql -BNe 'show databases' -u root -p<password>); do
    mysqldump -u root -p<password> $i | bzip2 > $i-`date +"%Y%m%d"`.sql.bz2;
    rm -rf $i-`date -d "-5 day" +"%Y%m%d"`.sql.bz2;
done > /dev/null 2>&1

Shoved that in my crontab. Works great. Linux rocks.

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