Update statistics operations affected by PDQ

An SQL UPDATE STATISTICS statement that is not processed in parallel, is affected by PDQ because it must allocate the memory used for sorting. Thus the behavior of the UPDATE STATISTICS statement is affected by the memory management associated with PDQ.

The database server must allocate the memory that the UPDATE STATISTICS statement uses for sorting.

If you have an extremely large database and indexes are fragmented, UPDATE STATISTICS LOW can automatically run statements in parallel. For more information, see Update statistics in parallel on very large databases.