Index for Section CONSTRAINTS

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SET
NAME
  SET CONSTRAINTS - set the constraint mode of the current transaction

SYNOPSIS
  SET CONSTRAINTS { ALL | name [, ...] } { DEFERRED | IMMEDIATE }

DESCRIPTION
  SET CONSTRAINTS sets the behavior of constraint evaluation in the current
  transaction. In IMMEDIATE mode, constraints are checked at the end of each
  statement. In DEFERRED mode, constraints are not checked until transaction
  commit.

  When you change the mode of a constraint to be IMMEDIATE, the new
  constraint mode takes effect retroactively: any outstanding data
  modifications that would have been checked at the end of the transaction
  (when using DEFERRED) are instead checked during the execution of the SET
  CONSTRAINTS command.

  Upon creation, a constraint is always give one of three characteristics:
  INITIALLY DEFERRED, INITIALLY IMMEDIATE DEFERRABLE, or INITIALLY IMMEDIATE
  NOT DEFERRABLE. The third class is not affected by the SET CONSTRAINTS
  command.

  Currently, only foreign key constraints are affected by this setting. Check
  and unique constraints are always effectively initially immediate not
  deferrable.

NOTES
  This command only alters the behavior of constraints within the current
  transaction. Thus, if you execute this command outside of a transaction
  block (BEGIN/COMMIT pair), it will not appear to have any effect. If you
  wish to change the behavior of a constraint without needing to issue a SET
  CONSTRAINTS command in every transaction, specify INITIALLY DEFERRED or
  INITIALLY IMMEDIATE when you create the constraint.

COMPATIBILITY
  This command complies with the behavior defined in the SQL standard, except
  for the limitation that, in PostgreSQL, it only applies to foreign-key
  constraints.

Index for Section CONSTRAINTS

Alphabetical listing for S

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