pt-find

Find MySQL tables and execute actions, like GNU find.

Find MyISAM tables:
pt-find --engine MyISAM <database>
Convert MyISAM to InnoDB
pt-find --engine MyISAM --exec "ALTER TABLE %D.%N ENGINE=InnoDB"
Find the largest tables and indexes, and sort by size:
pt-find --printf "%T\t%D.%N\n" <database> | sort -rn