Fb_lock_print is the utility which prints out details of the internal database lock page.

Gbak is the database backup & restore utility. It also allows various parameters internal to the database to be changed.

Gdef is a metadata utility which was removed from Interbase 4.0 and returned in the Open Source version 6. Gdef is probably redundant.

Gfix allows attempts to fix corrupted databases, starting and stopping of databases, resolving 'in limbo' transactions between multiple database, changing the number of page buffers and so on.

Gpre is the pre-processor which converts source code, which can be written in a number of languages, containing various embedded SQL 'pseudo code' into correctly formatted calls to the Firebird engine.

Gstat allows the Firebird administrator the ability to gather statistics about the general health and utilisation of various parts of the database.

Isql is the interactive utility that allows ad-hoc queries to be run against a Firebird database. It is console based - as are many of the utilities - and is supplied with all distributions of Firebird. Isql is usually the best place to try out your scripts and commands in the first instance.

Qli is the original Query Language Interpreter which was removed from Interbase 4.0 but returned in Interbase 6.0 because of the decision to Open Source Interbase.