--- title: "information_schema" description: "information_schema is a system catalog that presents metadata in the format used by SQL standard." menu: main: parent: 'system-catalog' weight: 3 --- Materialize has compatibility shims for the following relations from the SQL standard [`information_schema`](https://www.postgresql.org/docs/current/infoschema-schema.html) schema, which is automatically available in all databases: * [`applicable_roles`](https://www.postgresql.org/docs/current/infoschema-applicable-roles.html) * [`character_sets`](https://www.postgresql.org/docs/current/infoschema-character-sets.html) * [`columns`](https://www.postgresql.org/docs/current/infoschema-columns.html) * [`enabled_roles`](https://www.postgresql.org/docs/current/infoschema-enabled-roles.html) * [`key_column_usage`](https://www.postgresql.org/docs/current/infoschema-key-column-usage.html) * [`referential_constraints`](https://www.postgresql.org/docs/current/infoschema-referential-constraints.html) * [`role_table_grants`](https://www.postgresql.org/docs/current/infoschema-role-table-grants.html) * [`routines`](https://www.postgresql.org/docs/current/infoschema-routines.html) * [`schemata`](https://www.postgresql.org/docs/current/infoschema-schemata.html) * [`tables`](https://www.postgresql.org/docs/current/infoschema-tables.html) * [`table_constraints`](https://www.postgresql.org/docs/current/infoschema-table-constraints.html) * [`table_privileges`](https://www.postgresql.org/docs/current/infoschema-table-privileges.html) * [`triggers`](https://www.postgresql.org/docs/current/infoschema-triggers.html) * [`views`](https://www.postgresql.org/docs/current/infoschema-views.html) These compatibility shims are largely incomplete. Most are lacking some columns that are present in the SQL standard, or if they do include the column the result set its value may always be `NULL`. The precise nature of the incompleteness is intentionally undocumented. New tools developed against Materialize should use the documented [`mz_catalog`](../mz_catalog) API instead.