Parallel Execution -- 6 Parallel DML Restrictions

Here's link to the 11.2 documentation on Restrictions on Parallel DML

So, some of the implications are :

1.  You cannot do Parallel DML if a Trigger is present on the target table

2.  Certain integrity constraints disable Parallel DML.

3,  Parallel DML cannot be part of a Distributed Transaction.

Oracle silently converts the Parallel DML to a Serial DML without raising a warning / error.

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