Disabling a Constraint : Constraint « Table « Oracle PL/SQL Tutorial






By default, a constraint is enabled when you create it.

You can disable a constraint when you create it by adding DISABLE to the end of the CONSTRAINT clause.

SQL> -- create demo table
SQL> create table myTable(
  2    id           NUMBER(2),
  3    value        NUMBER(6,2)
  4  )
  5  /

Table created.


SQL>
SQL>
SQL> ALTER TABLE myTable
  2  ADD CONSTRAINT uq UNIQUE (id) DISABLE;

Table altered.

SQL>
SQL> ALTER TABLE myTable
  2  DISABLE CONSTRAINT uq;

Table altered.

SQL>
SQL> drop table myTable
  2  /

Table dropped.
SQL>








6.10.Constraint
6.10.1.Adding a Constraint
6.10.2.Add constaint for a date type column: larger than a certain date
6.10.3.Adding a 'NOT NULL' Constraint
6.10.4.The database automatically assigns a name to the constraint
6.10.5.Dropping a Constraint
6.10.6.Disabling a Constraint
6.10.7.Add CASCADE to the end of a DISABLE CONSTRAINT clause
6.10.8.Enabling a Constraint
6.10.9.You can also choose to apply a constraint to new data only by specifying ENABLE NOVALIDATE.
6.10.10.Deferred Constraints
6.10.11.How to drop a constaint
6.10.12.Violate a constraint
6.10.13.Cascade constraints