Set Constraints
Sets the constraint mode for the current transaction block.
Synopsis
SET CONSTRAINTS { ALL | constraint [,... ] }
{ DEFERRED | IMMEDIATE }
Parameters
ALL
The keyword indicating that the mode you are specifying should be applied to all constraints within the current transaction.
constraint
The name of a specific constraint for which you wish to set the mode.
DEFERRED
The keyword indicating that constraints (or a specific constraint) shouldnât be checked until the transaction reaches a
COMMIT
.IMMEDIATE
The keyword indicating that constraints (or a specific constraint) should be checked at the end of each statement within a transaction.
Results
SET CONSTRAINTS
The message returned when a constraint mode is set successfully.
ERROR: Constraint '
constraint
' does not exist
The error returned if you attempt to change the mode of a
constraint
that does not exist.
Description
Use the SET CONSTRAINTS
command to set the constraint mode for all
constraints or for a single constraint within the current transaction block. You can choose to
set the constraint mode to either IMMEDIATE
or DEFERRED
.
Use of IMMEDIATE
mode will force the checking of all constraints at the end
of each statement within the transaction. In DEFERRED
mode, constraints are
not checked until a COMMIT
command is issued.
Note
PostgreSQL 7.1.x (the most current version as of the writing of this book) only supports the use of these ...
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