Allows you to enable or disable all triggers, specified triggers,
    all constraints, specified constraints, a primary key, or a
    unique constraint, as described in the following list. By
    default, table and column constraints added during an alter table
    operation are enabled.

    o  DISABLE ALL TRIGGERS

       All triggers defined for the table are disabled. (No error is
       raised if no triggers are defined for this table.)

    o  ENABLE ALL TRIGGERS

       All triggers defined for the table are enabled. (No error is
       raised if no triggers are defined for this table.)

    o  DISABLE TRIGGER trigger-name

       The named trigger for this table is disabled. The named
       trigger must be defined on the table.

    o  ENABLE TRIGGER trigger-name

       The named trigger for this table is enabled. The named trigger
       must be defined on the table.

    o  DISABLE ALL CONSTRAINTS

       All table and column constraints for this table are disabled.
       (No error is raised if no constraints are defined on the
       table.)

    o  ENABLE ALL CONSTRAINTS

       All table and column constraints for this table are enabled.
       (No error is raised if no constraints are defined on the
       table.)

    o  DISABLE CONSTRAINT constraint-name

       The named constraint is disabled. The named constraint must be
       a table or column constraint for the table.

    o  ENABLE CONSTRAINT constraint-name

       The named constraint is enabled. The named constraint must be
       a table or column constraint for the table.

    o  DISABLE PRIMARY KEY

       The primary key for the table is disabled.

    o  ENABLE PRIMARY KEY

       The primary key for the table is enabled.

    o  DISABLE UNIQUE (column-name)

       The matching UNIQUE constraint is disabled. The columns listed
       must be columns in the table.

    o  ENABLE UNIQUE (column-name)

       The matching UNIQUE constraint is enabled. The columns listed
       must be columns in the table.

    o  VALIDATE and NOVALIDATE

       These options are available only on the enable-clause. By
       default, table and column constraints are enabled during an
       ALTER TABLE statement. When a constraint is added or enabled
       with the ALTER TABLE statement, the default is to validate
       the table contents. The ENABLE NOVALIDATE option allows a
       knowledgeable database administrator to avoid the time and I/O
       resources required to revalidate the data when he or she knows
       the data is valid.

                                      NOTE

          Oracle Corporation recommends that you use the RMU Verify
          command with the Constraint qualifier periodically to
          verify that your assumptions are correct if you use the
          ENABLE NOVALIDATE option.