# Checking database consistency

After you perform a backup, or if you experience hardware or operating system failure, you can use the `SYSCS_UTIL.SYSCS_CHECK_TABLE` system function to verify that the database is still consistent.

It is recommended that you run `SYSCS_UTIL.SYSCS_CHECK_TABLE` on all the tables in a database offline after you back it up. Do not discard the previous backup until you have verified the consistency of the current one. Otherwise, check consistency only if there are indications that such a check is needed, because a consistency check can take a long time on a large database.

See the Derby Reference Manual for details about this system function.

- The SYSCS_CHECK_TABLE function
  The SYSCS_UTIL.SYSCS_CHECK_TABLE function checks the consistency of a Derby table.
- Sample SYSCS_CHECK_TABLE error messages
  This section provides examples of error messages that the SYSCS_UTIL.SYSCS_CHECK_TABLE function can return.
- Sample SYSCS_CHECK_TABLE queries
  This section provides examples that illustrate how to use the SYSCS_UTIL.SYSCS_CHECK_TABLE function in queries.

Parent topic: Part Two: Derby Administration Guide
Related concepts
Maintaining database integrity
Backing up and restoring databases
Importing and exporting data
Replicating databases
Logging on a separate device
Obtaining locking information
Reclaiming unused space