user action

Database.md

@@ -135,12 +135,14 @@ Assignment table represents exercise assignment in a group. It holds keys of the
 
 ## UserAction
 
-- _user_ --
-- _loggedAt_ --
-- _action_ --
-- _params_ --
-- _code_ --
-- _data_ --
+Stores information about what routes on api user visited and some additional information about it.
+
+- _user_ -- which user performed api request
+- _loggedAt_ -- time when action was performed
+- _action_ -- action which was requested on api
+- _params_ -- GET or POST parameters given by user
+- _code_ -- return code which was sent back by api
+- _data_ -- if call ended up with an exception, description of thrown exception should be there
 
 ## UserSettings