Lowercase all tags:
Set all tags to lowercase for consistency
Recount tag use:
If the counts of images per tag get messed up somehow, this will reset them
Purge unused tags:
Get rid of all the tags that don't have any images associated with
them (normally they were created as typos or spam); this is mostly for
neatness, the performance gain is tiny...
Convert to InnoDB:
Convert your database tables to InnoDB, thus allowing shimmie to
take advantage of useful InnoDB-only features (this should be done
automatically, this button only exists as a backup). This only applies
to MySQL -- all other databases come with useful features enabled
as standard.
Database dump:
Download the contents of the database in plain text format, useful
for backups.