ORA-02294: cannot enable (string.string) - constraint changed during validation

ORA-02294
ORA-02294: cannot enable (string.string) - constraint changed during validation
Cause: While one DDL statement was attempting to enable this constraint,
another DDL changed this same constraint.
Action: Try again, with only one DDL changing the constraint this time.
More details : Viste http://www.high-oracle.com/ora-02294/
More details : Viste http://www.high-oracle.com/ora-02294/
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