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Does NOAPPEND hint disable Parallel DML for a MERGE statement?

in Database Tuning (MOSC) 3 commentsAnswered

Question: Does NOAPPEND hint disable Parallel DML for a MERGE statement? Is there a way to NOT move HWM with MERGE and Parallel DML?

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When running a very large nightly MERGE statement (inserts Millions of rows and updates millions of rows) I have noticed that when using parallel DML (using hint /* PARALLEL(8) ENABLE_PARALLEL_DML */), the inserts move up the high water mark (which is the default for INSERTS). This is a vendor nonpartitioned hash table, I don't want uncontrolled growth of this table nor rebuild it periodically. See plan below (steps 1 & 2 confirm we are using parallel DML)


Plan hash value: 328507775

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