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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.
Optimization when SQL is within an SPL routineIf an SPL routine contains SQL statements, the database server optimizes and executes the SQL within the SPL routine.
SQL optimizationIf an SPL routine contains SQL statements, at some point the query optimizer evaluates the possible query plans for SQL in the SPL routine and selects the query plan with the lowest cost. The database server puts the selected query plan for each SQL statement in an execution plan for the SPL routine.
Displaying the execution planWhen you execute an SPL routine, it is already optimized. You can display the query plan for each SQL statement contained in the SPL routine

Displaying the execution plan

When you execute an SPL routine, it is already optimized. You can display the query plan for each SQL statement contained in the SPL routine

To display the query plan, execute the SET EXPLAIN ON statement prior to one of the following SQL statements that always tries to optimize the SPL routine:

CREATE PROCEDURE
UPDATE STATISTICS FOR PROCEDURE
For example, use the following statements to display the query plan for an SPL routine:
```
SET EXPLAIN ON; 
UPDATE STATISTICS FOR PROCEDURE procname;
```