Issue Field Details - COMPUTED (SQL Expression) type field
These field types are calculated by the database 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 Number Of 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.
Some Display as choices will have a setting unique to that format e.g.:
Text - Number of lines
Numeric – Number of decimal digits
SQL Expression:
Can be any non-computed field name, constant, function, variable, and any combination of these connected by one or more operators. The expression cannot be a sub-query.
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. The RMTrack support team is available to assist you with the creation of any computed fields that you require.
