DB2 Query Patroller Administration Guide

Appendix B. Troubleshooting DB2 Query Patroller Clients

This chapter provides information to assist in troubleshooting the DB2 Query Patroller client and describes common problems that may be encountered.

The DB2 Query Patroller client may consist of the following tools: QueryEnabler, QueryMonitor, QueryAdministrator, and Tracker. Although there are different methods for troubleshooting each tool, because the tools are DB2 applications, methods used to troubleshoot DB2 clients as documented in the Troubleshooting Guide may often be applicable.

Troubleshooting QueryEnabler

The QueryEnabler is both an ODBC driver and an ODBC application. When trapping user queries, it acts as an ODBC application. When performing database access to DB2, it acts as an ODBC driver.

Whenever a problem occurs, you should check the following:

• the DB2 server is started

• the application can connect to the DB2 server directly using the DB2 cataloged names

• the QueryEnabler data source name is configured correctly to use the correct DB2 data source

• the application is using the correct QueryEnabler data source name

In order to help identify problems, IBM support representatives may employ the following tracing mechanisms collectively or separately:

• ODBC trace via the ODBC Data Source Administrator

• DB2 CLI trace

• DB2 trace

• DB2 QueryEnabler trace

The first three trace facilities are described in the Troubleshooting Guide. Refer to this document for detailed instructions.

DB2 QueryEnabler trace is enabled by editing the INI file DB2IWM.INI located in the Windows system directory and changing the value of LOG from FALSE to TRUE.

After this modification, the application accessing QueryEnabler should be restarted and the problem under investigation should be repeated to generate a diagnostic log called DB2IWM.LOG located in the root of the C partition, i.e. C:\DB2IWM.LOG.

This file will contain all ODBC function calls accessed in QueryEnabler by the application. QueryEnabler will continue to log information to this file until the LOG parameter in the DB2IWM.INI file is reset to FALSE. Ensure that there is sufficient free disk space on the C partition to support this file.

Common QueryEnabler Problems

1. The application is unable to connect to DB2:

   • Verify that the application is able to connect to DB2 using the DB2 data source names. If this fails, refer to the Troubleshooting Guide for information on how to resolve a connectivity problem.

   • Verify that the QueryEnabler data source is configured to use the correct DB2 data source.

   • Ensure that the user account and user passwords are correct.

2. The application is unable to access the QueryEnabler query submission dialogs:

   • Ensure the application is using the correct QueryEnabler data source name.

3. The QueryEnabler dialogs appear unexpectedly:

   • QueryEnabler will trap all DB2 queries through the ODBC interface except for queries accessing the DB2 system catalogs. Some applications will query DB2 in support of the application. These queries supplement the main user query. QueryEnabler cannot distinguish between the main user query and the supplemental query. In this event, select the Submit and Wait button to execute these queries. This allows time for the result set to be constructed and unwanted QueryEnabler dialogs do not appear.

4. The query application is unable to submit a query to the DB2 Query Patroller server using QueryEnabler:

   • Ensure the DB2 Query Patroller server stored procedures have been installed on the DB2 server.

   • Ensure the user has been granted the proper DB2 access to the stored procedures.

5. The application has submitted a query to the DB2 Query Patroller server but the query is not being executed:

   • Ensure that the DB2 Query Patroller server is running correctly. It may be necessary to restart the DB2 Query Patroller server.

   • Use QueryMonitor to inspect the details of the Job. The job may be held because the query exceeded user thresholds. An DB2 Query Patroller administrator or operator must be contacted to release this job.

   • The job may be in the queue state because system resources have exceeded configured limitations. Under these conditions, the query will execute once the system resources fall within acceptable limits as configured by the DB2 Query Patroller administrator.

Troubleshooting QueryMonitor and QueryAdministrator

QueryMonitor and QueryAdministrator are Java applications that access DB2 using JDBC. Diagnostic information can be obtained from four sources:

• the DB2 diagnostic log

• ODBC traces

• CLI traces

• DB2 traces

Typically those trace tools are launched using a Java Virtual Machine (JVM) that does not have a console (JREW.EXE). These trace tools may also be run in a JVM that has a console (JRE.EXE), in which case DB2 Query Patroller will print information to the console. You can use that information to help identify the cause of a problem.

Common QueryMonitor and QueryAdministrator Problems

1. The tool is unable to connect to DB2:

   • Ensure that the DB2 data source name is used in the connect dialog.

   • Ensure that you have supplied the correct user name and password.

2. The application stops responding:

   • Close and restart the application. If the problem persists, attempt to run the application from a JVM with a console to obtain additional diagnostic information.

Troubleshooting Tracker

Tracker is an ODBC application that accesses the DB2 Query Patroller schema in DB2 in order to provide reports that display database usage history for queries that have been managed by DB2 Query Patroller.

Diagnostic information for Tracker can be obtained from four sources:

• the DB2 diagnostic log

• ODBC traces

• CLI traces

• DB2 traces

Common Tracker Problems

1. Tracker is unable to access DB2:

   • Ensure that the correct DB2 data source name, user name, and password have been specified.

2. Tracker does not display any data:

   • Ensure that the DB2 Query Patroller server has been configured to capture this information.

   • From QueryAdministrator, check that the Accounting option has been enabled.

   • Ensure that the date range specified in the Tracker application is set correctly to a time period when queries were in progress.

3. The data displayed by Tracker is not up-to-date:

   • Ensure the Tracker server on the DB2 Query Patroller server is scheduled to execute periodically. The Tracker server component may be executed interactively to generate up-to-date statistics.

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