Information Schema REFERENTIAL_CONSTRAINTS Table

The Information Schema REFERENTIAL_CONSTRAINTS table contains information about foreign keys. The single columns are listed in the KEY_COLUMN_USAGE table.

It has the following columns:

ColumnDescription
CONSTRAINT_CATALOGAlways def.
CONSTRAINT_SCHEMADatabase name, together with CONSTRAINT_NAME identifies the foreign key.
CONSTRAINT_NAMEForeign key name, together with CONSTRAINT_SCHEMA identifies the foreign key.
UNIQUE_CONSTRAINT_CATALOGAlways def.
UNIQUE_CONSTRAINT_SCHEMADatabase name, together with UNIQUE_CONSTRAINT_NAME and REFERENCED_TABLE_NAME identifies the referenced key.
UNIQUE_CONSTRAINT_NAMEReferenced key name, together with UNIQUE_CONSTRAINT_SCHEMA and REFERENCED_TABLE_NAME identifies the referenced key.
MATCH_OPTIONAlways NONE.
UPDATE_RULEThe Update Rule; one of CASCADE, SET NULL, SET DEFAULT, RESTRICT, NO ACTION.
DELETE_RULEThe Delete Rule; one of CASCADE, SET NULL, SET DEFAULT, RESTRICT, NO ACTION.
TABLE_NAMETable name from the TABLE_CONSTRAINTS table.
REFERENCED_TABLE_NAMEReferenced key table name, together with UNIQUE_CONSTRAINT_SCHEMA and UNIQUE_CONSTRAINT_NAME identifies the referenced key.

Comments

Comments loading...
Content reproduced on this site is the property of its respective owners, and this content is not reviewed in advance by MariaDB. The views, information and opinions expressed by this content do not necessarily represent those of MariaDB or any other party.