JDBC trace configuration

If the application displays JDBC-related exception messages, activate the JDBC trace service. The resulting log text can help you identify the problem.

Turn on tracing for most database JDBC implementations through the administrative console; see the topic, Enabling trace at server startup for instructions.

(ZOS) Turn on tracing for most database JDBC implementations through the administrative console; see the article Enabling trace, for instructions.

This method activates JDBC trace for all applications that run in the server we specify. Identify the database type by selecting the trace group WAS.database and typing one of the following trace strings in the console:

• com.ibm.ws.database.logwriter Trace string for databases that use the GenericDataStoreHelper. We can also use this trace string for unsupported databases.
• com.ibm.ws.db2.logwriter Trace string for DB2 databases.
• com.ibm.ws.oracle.logwriter Trace string for Oracle databases.
• com.ibm.ws.derby.logwriter Trace string for Derby databases.
• com.ibm.ws.informix.logwriter Trace string for Informix databases.
• com.ibm.ws.sqlserver.logwriter Trace string for Microsoft SQL Server databases.
• com.ibm.ws.sybase.logwriter Trace string for Sybase databases.

A few JDBC drivers require that we set trace differently, at the data source level. These drivers include:

• Microsoft SQL Server JDBC driver
• DataDirect Connect for JDBC driver for MS SQL Server

Configuring trace for these drivers through the WAS.database group results in corrupt trace information. The application server sets trace for the group at the server level, causing the trace service to begin only after the application establishes an initial connection. Because that first connection does not carry trace information, re-use of it is never tracked. Consequently the application cannot accurately match trace information to connection use.

Set trace for the previously mentioned JDBC drivers through data source custom properties. For example, use the spyAttributes custom property to enable JDBC trace for the DataDirect Connect for JDBC driver. Consult your driver documentation for details on the custom property that enables trace for our JDBC implementation.

Provider-specific configuration

Some JDBC providers have custom properties and configuration settings that we can use to tweak their trace settings.

• DB2 data sources

  The custom properties for a data source with DB2 Data Server Driver for JDBC and SQLJ are:

  traceLevel

  The possible values for traceLevel are:

  • TRACE_NONE = 0
  • TRACE_CONNECTION_CALLS = 1
  • TRACE_STATEMENT_CALLS = 2
  • TRACE_RESULT_SET_CALLS = 4
  • TRACE_DRIVER_CONFIGURATION = 16
  • TRACE_CONNECTS = 32
  • TRACE_DRDA_FLOWS = 64
  • TRACE_RESULT_SET_META_DATA = 128
  • TRACE_PARAMETER_META_DATA = 256
  • TRACE_DIAGNOSTICS = 512
  • TRACE_SQLJ = 1024
  • TRACE_XA_CALLS = 2048
  • TRACE_META_CALLS = 8192
  • TRACE_DATASOURCE_CALLS = 16384
  • TRACE_LARGE_OBJECT_CALLS = 32768
  • TRACE_SYSTEM_MONITOR = 131072
  • TRACE_TRACEPOINTS = 262144
  • TRACE_ALL = -1

  Trace of Statement calls will expose the user data in sets to the PreparedStatement objects, and Trace of ResultSet calls will expose data returned in gets from the ResultSet objects.

  traceFile

  To integrate the DB2 Data Server Driver for JDBC and SQLJ trace with the application server's trace function:

  • If we do not set the value, traces are integrated.

    If we use integrated trace, we can dynamically enable or disable trace by setting the following property in the application server's trace specification at run time:

    WAS.database=all
    

  • If we set the traceFile property to a valid path name for a file, then the Data Server Driver trace is written to the specified file regardless of the application server's trace specification.

  traceFileAppend

  Append to or overwrite the file specified by the traceFile property:

  • To append to the current file, set the property to true.

  • To overwrite the current file, set the property to false.

  If we change the values for traceLevel, traceFile, or traceFileAppend, then the we must restart the application server to instantiate new data source objects with the changed settings.

Additional resources

If the JDBC tracing service cannot help you isolate and fix our problem, consult the IBM Support website for WebSphere Application Server. Use the site search function to find current information on known problems and their resolutions. Locating the right troubleshooting tip can save time that we might otherwise spend on opening and tracking a PMR.

Data access problems

Enable trace at server startup