Issue Field Details - COMPUTED (SQL Expression) type field
Computed Field Settings
These field types are calculated by the database engine as a result of an SQL expression. A computed field is a virtual field that is not physically stored in the Issues table. For example, a computed field "Days Open" could be derived from an expression using the date opened field and the current date.
Display as:
The format (data type) of the result of the expression. Two Display as choices have a setting unique to that format:
Text - Number of lines
Numeric – Number of decimal digits
SQL Expression:
Can be any non-computed field name in the Issues table of the database, a constant, a function, a variable, and any combination of these connected by one or more operators.
Toggle editor:
This will toggle between a simple text entry and a more robust editor. The editor has options for full screen mode, undo/redo, and go to line #. It is useful when writing more complex queries
During the save of a computed field, simple syntax errors will be detected i.e. referencing nonexistent fields, functions and operators, and incorrect use of functions and operators. The more difficult to detect semantic errors and errors caused by a mismatch between the expression and the Display as setting (see below) will not occur until runtime. When errors are detected at runtime, the field value will display as **error**on both the issue list and the issue details pages.
By definition, computed fields cannot be updated, they are calculated by the database engine. Therefore, Field Level Security can never be set to Update permission, only Inquiry or None.
NOTE: Computed fields require some knowledge of databases and SQL expressions. Please feel free to contact support@rmtrack.com or log a support request on the RMTrack Support site for assistance.
