The following fields are currently available:

• Hostname
  Hostname of the user who triggered the event.

• Location
  URL of the origin of the event.

• Message
  The actual message of the log entry.

• Operations
  Operation links for the event.

• Referer
  URL of the previous page.

• Severity level
  The severity level of the event; ranges from 0 (Emergency) to 7 (Debug).

• Timestamp
  Date when the event occurred.

• Type
  The of the log entry, for example "user" or "page not found.".

• UID
  The user ID of the user on which the log entry was written.

• Variables
  The variables of the log entry in a serialized format.

• WID
  Unique watchdog event ID.