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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.
Queries and the query optimizerThese topics describe query plans, explain how the database server manages query optimization, and discuss factors that you can use to influence the query plan. These topics also describe performance considerations for SPL routines, the UDR cache, and triggers.
Factors that affect the query planWhen the optimizer determines the query plan, it assigns a cost to each possible plan and then chooses the plan with the lowest cost. The optimizer analyzes several factors to determine the cost of each query plan.
Effect of PDQ on the query planWhen the parallel database query (PDQ) feature is turned on, the optimizer can choose to execute a query in parallel. This can improve performance dramatically when the database server processes queries that decision-support applications initiate.

Effect of PDQ on the query plan

When the parallel database query (PDQ) feature is turned on, the optimizer can choose to execute a query in parallel. This can improve performance dramatically when the database server processes queries that decision-support applications initiate.

For more information, see Parallel database query (PDQ).