DB Check
Access this module in the TYPO3 backend under System > DB Check.
Record statistics
Gives you an overview of how many pages of which type and how many records of any table are present in the current system.
Database Relations
Gives an overview of the count of lost relations in select and group fields
Full Search
Search the complete database or specific table / field combinations and offers you detail and edit links to jump directly to the records found.
Manage Reference Index
Can be used on smaller installations to check or update the reference index.