DBRotator

Easy MySQL database rotation and pruning -- downloads and imports a mysql dump, and then deletes all but N databases, keeping only the newest. This tool is geared toward rotating out achived MySQL backups to your local dev environment. So it works best when you have a most-current MySQL backup as a symlink that updates nightly.

gem install db-rotator

• This tool creates and drops databases, and runs any SQL in your dump (duh), so you have to give it a user that can do all of that. If you're using this on a local dev environment, it's recommended to setup user/pass in ~/.my.cnf so that "mysql" works without -u or -p. You can configure DBRotator to work with any credentials, however. See config section.
• Disk space for N+1 database instances, where N is the amount you want to prune to (maximum DBs).

Minimal usage:

Run: db-rotator -p 'appdump_' -c 'scp db5:/opt/backups/latest.sql.bz2'

Or, from default config file ~/.db-rotator.yml:

db_prefix: "appdump_"
scp_command: "scp db5:/opt/backups/latest.sql.bz2"

Run: db-rotator

Or, from a specific config file /whatever/rotator-config.conf:

db_prefix: "appdump_"
scp_command: "scp db5:/opt/backups/latest.sql.bz2"

Run: db-rotator -f /whatever/rotator-config.conf

Rotate nightly, so you'll always have a fresh dump during your workday:

0 3 * * * bash -lc "db-rotator -f /whatever/rotator-config.conf >> /some/log/file"

Run db-rotator without any options to show config options.

Database naming prefix that will apply to all dumps rotated with DBRotator. Example: myproject_, which might name a DB as myproject_09182013.

How DBRotator retrieves your dumps. This ideally is an scp command, but really can be any command that receives a second argument of the dump destination. Example: scp hostname:/path/to/mysql/backups/backup_filename.sql.bz2

• local_dump_destination (-d). Where to put the dump, as a directory. The dump won't be deleted after running rotator. Default: /tmp
• mysql_command (-m). Used for all database management operations. Default: mysql
• maximum_dbs (-n). Maximum number of DBs to maintain, or null to disable pruning. Default: 2
• unarchive_command (-u). How to unarchive your dump to standard output. Default: bzip2 -cd
• unarchive_extra_pipe (-i). Any extra script(s) you want to run between unarchive & import. Example: ["/some/filter/for/imported_data", "/some/other/filter/for/imported_data"] Default: nil
• reasonable_diskspace (-s). Rough estimate of temporary disk space required to import a typical dump, in GB. Ensures this amount of space is free before importing. Default: nil
• rails_db_yaml_path (-y). Updates database name in your YAML file. Example: /path/to/railsroot/config/database.yml Default: nil
• rails_environments (-e). In conjunction with -y, which rails envs to update DB name for. If passing multiple via command line, use a comma to separate, like -e "development,staging". Default: ["development"]
• on_success (-S). Executes COMMAND on successful completion
• on_failure (-F). Executes COMMAND if there is an error