When working with Oracle database, you may encounter the error : ORA-02429: cannot drop index used for enforcement of unique/primary key. This tutorial will show you how to solve this problem.

As stated in the documentation,  Oracle Database enforces a  UNIQUE key or  PRIMARY KEY integrity constraint on a table by creating a unique index on the unique key or primary key. This index is automatically created by the database when the constraint is enabled.  The ORA-02429 error happens when you attempt to drop the index with first dropping the constraint (primary key)

Solution:

You need to drop unique or primary key constraint.

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