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As you can see at this link sometimes the PARALLEL HINT doesn't work in forking parallel execution of an update query.

For select I must even force a FULL TABLE SCAN or a FAST FULL INDEX SCAN. How does it work for DML statement?

I used the directive alter session enable parallel dml;

If you look at the IO of the linked topic. Just one thread is making read / changes.

Seanny123
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Revious
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1 Answers1

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Oracle only uses parallel execution for UPDATE or DELETE statements when they affect multiple partitions. Both variants of your query seem to include the partition key in their sub-queries: are you certain that the values in the temporary tables will cover several partitions?

APC
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