About defining computed columns and computed fields

When creating a form, you can define computed columns and computed fields:

In the Select painter, you can define computed columns when you are defining the SELECT statement that will be used to retrieve data into the form
In the Form painter, you can define computed fields after you have defined the SELECT statement

The difference between the two ways

When you define a computed column in the Select painter, the column’s definition is part of the SELECT statement and the value is calculated by the DBMS when the data is retrieved. The computed column’s value does not change until data has been updated and retrieved again.

When you define a computed field in the Form painter, the value of the column is calculated by InfoMaker in the form after the data has been retrieved. The value changes dynamically as the data in the form changes.

Recommendation

If you want your DBMS to do the calculations on the server before bringing data down and you do not care about dynamically updating the computed values, define computed columns as part of the SELECT statement.

If you want computed values to change dynamically, define computed fields in the Form painter, as described next.