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RDB/VMS SQL SET_ALL_CONSTRAINT — VMS RDB_4.0B

 SET ALL CONSTRAINTS ─┬─> 
O

N
───┬──> └─> 
O

F

F
──┘

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 Controls constraint checking for constraints that are evaluated
 at commit time.  (This statement has no effect on constraints
 that are evaluated at verb time.) A major use of the SET ALL
 CONSTRAINTS statement is to permit evaluation of these
 constraints at intervals before the transaction is committed.

 The default setting for the SET ALL CONSTRAINTS statement is OFF
 (that is, constraint evaluation is deferred until commit time)
 -- unless you have specified otherwise with the
 /SQLOPTIONS=(CONSTRAINTS=ON) qualifier on the SQL precompiler
 command line, or with the /CONSTRAINTS=ON qualifier on the SQL
 module language command line.

 Setting constraints ON causes all of the affected constraints to
 be evaluated immediately, as well as at the end of each
 statement -- until the SET ALL CONSTRAINTS OFF statement is
 issued or until the transaction completes with a commit or
 rollback operation.

 Setting constraints OFF causes constraint evaluation to be
 deferred until commit time.  This is the initial and default
 setting for the SET ALL CONSTRAINTS statement.

 If a transaction has been declared but is not active when the
 SET ALL CONSTRAINTS statement is executed, SQL starts the
 declared transaction.

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