INITIALLY Clause The INITIALLY clause establishes the default checking behavior
for constraints that are DEFERRABLE. The INITIALLY setting can be overridden by a
SET CONSTRAINT(S) statement in a subsequent transaction.
■ Specify INITIALLY IMMEDIATE to indicate that Oracle should check this
constraint at the end of each subsequent SQL statement. If you do not specify
INITIALLY at all, then the default is INITIALLY IMMEDIATE.
See Also:
■ SET CONSTRAINT[S] on page 19-48 for information on setting
constraint checking for a transaction
■ Oracle Database Administrator's Guide and Oracle Database Concepts
for more information about deferred constraints
■ "DEFERRABLE Constraint Examples" on page 8-25
constraint
Common SQL DDL Clauses 8-15
If you declare a new constraint INITIALLY IMMEDIATE, then it must be valid at
the time the CREATE TABLE or ALTER TABLE statement is committed or the
statement will fail.
■ Specify INITIALLY DEFERRED to indicate that Oracle should check this constraint
at the end of subsequent transactions.
This clause is not valid if you have declared the constraint to be NOT DEFERRABLE,
because a NOT DEFERRABLE constraint is automatically INITIALLY IMMEDIATE and
cannot ever be INITIALLY DEFERRED.
DEFERRED IMMEDIATE
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