Controls whether or not MESSAGE statements that include a DEBUG ONLY clause are executed.
This option allows you to control the behavior of debugging messages in stored procedures that contain a MESSAGE statement with the DEBUG ONLY clause specified. By default, this option is set to OFF and debugging messages do not appear when the MESSAGE statement is executed. By setting DEBUG_MESSAGES to ON, you can enable the debugging messages in all stored procedures.
DEBUG ONLY messages are inexpensive when the DEBUG_MESSAGES option is set to OFF, so these statements can usually be left in stored procedures on a production system. However, they should be used sparingly in locations where they would be executed frequently; otherwise, they might result in a small performance penalty.