Schema

Introduced in Drupal 6, the Schema API allows modules to declare their database tables in a structured array (similar to the Form API) and provides API functions for creating, dropping, and changing tables, columns, keys, and indexes.

The Schema module provides additional Schema-related functionality not provided by the core Schema API that is useful for module developers. Currently, this includes:

• Schema documentation: hyperlinked display of the schema's embedded documentation explaining what each table and field is for.
• Schema structure generation: the module examines the live database and creates Schema API data structures for all tables that match the live database.
• Schema comparison: the module compares the live database structure with the schema structure declared by all enabled modules, reporting on any missing or incorrect tables.

Note for MySQL users: The Schema module requires MySQL 5. Prior versions of MySQL do not support the INFORMATION_SCHEMA database that the Schema module uses to inspect the database.

Related modules

• Schema reference field: adds a new field type that uses Schema to let you refer to database connections, tables, and/or columns.