Configuring query service properties

The query service uses environment, logging, and tuning configuration settings.

About this task

A summary of the query service settings can be viewed on the Settings - Query Service pane. You can configure properties for the query service.

Procedure

Launch IBM Cognos Administration, and from the Status tab select System.
On the Scorecard section, click the All servers list, point to Services, and then click Query.
From the QueryService list, click Set properties.
Click the Settings tab.

In the Value column, type or select the value for the settings that you want to change. The following table describes the properties that you can set for the query service.

Option	Description
Advanced Settings	Click Edit to specify advanced configuration settings. Because an entry acquires advanced settings from a parent, editing these settings overrides the acquired advanced settings. For information about types of advanced settings, see the IBM Cognos Administration and Security Guide.
Audit logging level for query service	Select the level of logging that you want to use for the query service.
Enable query execution trace	A query execution trace (run tree trace) shows queries that run against a data source. You use the trace to troubleshoot query-related issues. You can find execution trace logs in the following location: `c10_location`/logs/XQE/`reportName`/runtreeLog.xml. For more information about the query execution trace, see the IBM Cognos Dynamic Query Guide . You can view and analyze these log files using IBM Cognos Dynamic Query Analyzer. For more information, see the IBM Cognos Dynamic Query Analyzer User Guide.
Enable query planning trace	Query plan tracing (plan tree) captures the transformation process of a query. You can use this information to gain an advanced understanding of the decisions and rules that are executed to produce an execution tree. The query planning trace is logged for every query that runs using dynamic query mode. You can find planning trace logs in the following location: `c10_location`/logs/XQE/`reportName`/plantreeLog.xml. Since planning logs are large, there is an impact on query performance when this setting is enabled. For more information about the query planning trace, see the IBM Cognos Dynamic Query Guide .
Generate comments in native SQL	Specifies which reports are generating the SQL queries in the database.
Write model to file	Specifies whether the query service will write the model to a file when a query runs. The file is used only for troubleshooting purposes. Modify this property only with the guidance of IBM® Software Support. You can find the file in the following location: `c10_location`\logs\model\`packageName`.txt
Idle connection timeout	Specifies the number of seconds to maintain an idle data source connection for reuse. The default setting is 300. Valid entries are 0 to 65535. Lower settings reduce the number of connections at the expense of performance. Higher settings might improve performance but raise the number of connections to the data source.
Minimum query execution time before a result set is considered for caching	Specify the minimum amount of time to wait for a query before caching the results. This setting does not apply to dynamic cubes.
Initial JVM heap size for the query service	Specifies the initial size, in MB, of the Java Virtual Machine (JVM) heap.
JVM heap size limit for the query service	Specifies the maximum size, in MB, of the JVM heap.
Initial JVM nursery size	Specifies the size, in MB, that the JVM allocates to new objects. The nursery size is automatically calculated. This setting does not need to be changed. The only situation in which this setting needs to change is if you are in consultation with IBM Cognos customer support and they recommend a specialized change.