Message logging

You can use the logMsg() facility to include operational messages and debugging hints within your UDXs. The logMsg facility is similar to printf-style logging. You add the messages that you want to track the operation of the UDX. Each message has a flag value (LOG_DEBUG, LOG_TRACE, or both values OR’ed together) to help you control the verbosity of the output.

You can control how much detail is output for a specific UDF or UDA by using the LOGMASK attribute when you register the function or aggregate, or when you run the UDX by using the test harness.