`information_schema.referential_constraints.constraint_catalog`

mysql

type: VARCHAR NOT NULL

5.7-8

type: NULL

Note:

Always def.

5.1-10.8

type: VARCHAR NOT NULL

Note:

Always def.

type: SQL_IDENTIFIER NULL

Note:

Name of the database containing the constraint (always the current database)

10-15

type: SQL_IDENTIFIER

Note:

Name of the database containing the constraint (always the current database)

7.4-9.6

type: unknown

Note:

Name of the database containing the constraint.

2-21.2

type: NVARCHAR(128) NULL

Note:

Constraint qualifier.