You can also choose to apply a constraint to new data only by specifying ENABLE NOVALIDATE. : Constraint « Table « Oracle PL/SQL Tutorial






  1. Oracle PL/SQL Tutorial
  2. Table
  3. Constraint

The default is ENABLE VALIDATE.

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

Table created.

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

Table altered.

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

Table altered.

SQL>
SQL>                                                                                                                                                                   Null?    Type
SQL> ALTER TABLE myTable
  2  ENABLE NOVALIDATE CONSTRAINT uq;

Table altered.

SQL>
SQL>
SQL>
SQL> drop table myTable
  2  /

Table dropped.

SQL>
SQL>
SQL>
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