The table editor window, titled with the name of the table you are editing. A column is defined as computed column by selecting the computed column option of a column in the table editor A computed column is defined by an expression, whether from regular columns in the same row, functions, arithmetic operators, or path names.
This option is available only in Adaptive Server® Enterprise
versions 15 and later.
To designate a column as computed, select Computed Column in the table editor window. This displays the property sheet of the column, with the focus on the Computed Columns tab.
If you select Computed Column, Datatype is dimmed; you cannot edit Size and Scale fields, either.
In the new computed column, you can:
Enter the column expression in the Computed Column Expression field.
Select either Non-Materialistic (Virtual) or Materialistic.
When you select the Computed Column tab in the Column property sheet, these options are not applicable:
Rules and Defaults
Check Constraints
Primary Key
These options are disabled because Computed Columns are non-materialistic by default, which prevents them from any involvement in constraints, rules, and defaults. Select Materialistic to reenable these options.
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