The "System Messages" screen registers and changes system messages. A system message is a text that is shown when an error occurs during the processing of a change. Error messages from the software use an internal error code. The message translates this internal code into a comprehensible text. Registering messages is a typical activity for application developers. See the warning under Application Development. The entry fields have the following meaning: - "Code": The internal code that refers to the message. - "User Message": The message that is displayed. The application translates this message with [[Invantive Estate/Subjects/Advanced/Translations|Translations]]. - "Constraint Code": The database error code from the software. These error codes usually have the format `ORA-99999`. - "Constraint Name": A reference to the exact location of the message. Part of the database error codes carries such a reference. When the program translates a database error code to a message, it first checks whether the combination of constraint code and constraint name already exists: - If so, the respective message is used. - If not, a general constraint code is looked for, without a filled-out constraint name.