Format Domains
A format domain is like an alpha domain, except that its primary characteristic is an edit mask.
The Format Domain overlay, shown in Figure 2-3-7, displays after you complete the entries on the Domains screen if the domain Type you select is FORMAT.
Figure 2-3-7. Format Domain Overlay
The Format Domain overlay contains the following fields:
· Edit Mask establishes format requirements for data validation and also determines how the field is stored and displayed. A mask character representing the allowable values is entered for each position in the field. The mask characters are:
# (numbers only)
@ (letters only)
& (numbers and letters only)
! (any characters)
* (use default value character) — The valid character for this position in a mask is defined by referencing the same position in the default value.
For example, you can mask a phone number field with the following entry: ###*###*####.
· Default Value establishes a starting value for all referenced fields whenever they are first displayed in add mode in an input image, unless modified by a user. If blank, there is no starting value displayed on the image. The positioning of constant characters in the default value must correspond to the positions of *s, if any, in the edit mask. For example, a possible default value for the phone number mask indicated in Edit Mask earlier is: _ _ _ - _ _ _ - _ _ _ _ (the underlines represent blanks).
· Lowercase OK? indicates whether or not a modifiable item
on an interactive screen can be entered in upper- and lowercase letters.
If “no” 
, the entry is stored and displayed exclusively
as uppercase, regard-less of how a user enters the information. This entry
does not affect statements. A lowercase value established with a statement
displays as lowercase, even if this specification prohibits lowercase
entries. The default is “yes” 
.
· Descriptive provides a longer, more easily understood alternative to Domain Name, one that is not required to be unique within an application. If blank at all default levels, Domain Name is used.
· Column Hdgs designates up to two lines of column heading text. The APPX output process facility uses this text to generate standard column heading images for Start of Page and Start of Range class frames. For cosmetic reasons, the length of headings should not exceed the length of a domain itself. Refer to Standard Column Heading Image for additional information.
For Format domain type, the following options are available as described in the corresponding sections: