The REFERENTIAL_CONSTRAINTS
table
provides information about foreign keys.
The REFERENTIAL_CONSTRAINTS
table has
these columns:
CONSTRAINT_CATALOG
The name of the catalog to which the constraint belongs. This value is always
def
.CONSTRAINT_SCHEMA
The name of the schema (database) to which the constraint belongs.
CONSTRAINT_NAME
The name of the constraint.
UNIQUE_CONSTRAINT_CATALOG
The name of the catalog containing the unique constraint that the constraint references. This value is always
def
.UNIQUE_CONSTRAINT_SCHEMA
The name of the schema containing the unique constraint that the constraint references.
UNIQUE_CONSTRAINT_NAME
The name of the unique constraint that the constraint references.
MATCH_OPTION
The value of the constraint
MATCH
attribute. The only valid value at this time isNONE
.UPDATE_RULE
The value of the constraint
ON UPDATE
attribute. The possible values areCASCADE
,SET NULL
,SET DEFAULT
,RESTRICT
,NO ACTION
.DELETE_RULE
The value of the constraint
ON DELETE
attribute. The possible values areCASCADE
,SET NULL
,SET DEFAULT
,RESTRICT
,NO ACTION
.TABLE_NAME
The name of the table. This value is the same as in the
TABLE_CONSTRAINTS
table.REFERENCED_TABLE_NAME
The name of the table referenced by the constraint.