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AdministeringIn addition to administering the database server, you can tune performance, replicate data, and archive data.
System administrationThese topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL OneDB™ database servers.
Performance GuideThe HCL OneDB™ Performance Guide describes how to configure and operate your HCL OneDB™ database server to improve overall system throughput and to improve the performance of SQL queries.
Parallel database query (PDQ)You can manage how the database server performs PDQ and you can monitor the resources that the database server uses for PDQ.
Database server operations that use PDQHCL OneDB™ processes some types of SQL operations that the database server processes in parallel. However some situations limit the degree of parallelism that HCL OneDB™ can use.
Update statistics operations affected by PDQAn 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.

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.