REFERENCES Clause

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REFERENCES Clause

The REFERENCES clause has the following syntax.

REFERENCES Clause:
 
|--REFERENCES--table--+------------------+---------------------->
                      |    .-,------.    |
                      |    V        |    |
                      '-(----column-+--)-'
 
>--+--------------------------+---------------------------------|
   |  (1)                     |
   '--------ON DELETE CASCADE-'

Notes:

Informix extension

Element	Description	Restrictions	Syntax
column	Referenced column in the referenced table	See Restrictions on Referential Constraints.	Identifier, p. Identifier
table	The referenced table	The referenced and the referencing tables must reside in the same database	Database Object Name, p. Database Object Name

The REFERENCES clause allows you to place a foreign-key reference on a column. The referenced column can be in the same table as the referencing column, or in a different table in the same database.

If the referenced table is different from the referencing table, the default column is the primary-key column. If the referenced table is the same as the referencing table, there is no default.