Controls the format of messages written to the log file and which fields appear in them.
If the message string contains any of the following codes, the current values are substituted for the codes as each message is written.
The @ character
Date and time that processing of the request started, unless the request cannot be queued due to an error
Date and time that the client connected
Name of the database associated with the request
Text of the error message, if an error occurred
Date and time that processing of the request finished
IP address of the client
Length of the response, in bytes, including headers and body
HTTP request method
Listener port associated with the request
Date and time that the request was queued for processing, unless the request could not be queued due to an error
Status code and description of the HTTP response
HTTP status code
Date and time that the current log entry was written
Requested URI
Requested HTTP version
Time taken to process the request (@F – @B), or 0.000 if the request was not processed due to an error