Defining the Contents of a Calculated Field
When you create a calculated field, a formula builder will open. The formula builder is the dialog where you specify the actual formula, as well as other field definitions, such as field name and type.
When you create or edit a calculated field, you can change the field name using the "Name" text box at the top left of the dialog. In addition to the dynamic nature of the calculation, the field name also changes in the table as you type. In the example above, the calculated field name is "Total."
As with standard fields, calculated fields also need to have a data type associated with them. A data type is automatically generated depending on the formula that you use. This automatic setting is signified by the word "Auto" in the "Type" drop-down box on the top of the dialog. However, you may also change the type setting manually if you wish. This is usually not necessary for normal use; however, it is important to have in certain circumstances, particularly when interacting with external database systems. Click on the drop-down menu and select from the following types:
Field Width and Decimal Precision
The field width default is set to 30 characters for character and date types, 18 characters and 2 decimal places for numeric types, and 1 character for Boolean types.
However, you can edit these values to any number you wish to choose by clicking on the "Width" and "Decimal" text boxes and changing the value, either by manually typing in the new number or by using the arrows to increase or decrease the number.
The formula box is the place where you enter your formula. You can type the formula in directly or you can also double-click on the helper items, such as the function names, field names and operators located underneath the formula box. Click here for further information on using formulas.
Formula Builder Help
The formula builder also has some built-in functionality to help you build your formulas: