Inserting Custom Messages in Oracle Alert/Trace files

DBMS_SYSTEM package that allows us to insert our own customized messages in Alert log and/or trace files. I tried this feature and found it to be quite powerful as regards its usage.

Routines in DBMS_SYSTEM package
The following routines can be used to write vital information to Alerts and Trace files.

• KSDIND:
  Does an indent in the form of inserting colons (:) before the next write is carried out. The indent levels are from 0 to 30. This option could be used to separate the custom messages from the existing oracle messages. For example, I could search the Alert Log for messages starting with 5 colons to identify Application generated messages. The default is 0. This process fails to work in some cases (mentioned below). As a safety, I also add a standard prefix to all messages to identify application related messages.
  
• KSDWRT:
  Writes a message to the alert file. The first parameter DEST takes input as 1 (write to trace file), 2 (write to alert log) or 3 (write to both trace and alert log files). The second parameter TST is the actual text message that should go into the file(s).
  

Example

SQL> exec dbms_system.ksdwrt(2, 'testing for alert log writing');

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