Chapter 2-1: Data Dictionary Overview

Mask Definition

Masks are symbolic representations of fields. Each character position has a specific meaning with regard to the data it can store or display. Masks represent a visual approach to data definition, or data painting. When appropriately designed, masks enhance the ease of use and operation of an application, and the readability of displays and printed output, and they minimize the space that is required to store and display data.

You establish edit masks for format domains and fields. APPX uses the edit mask as a basis for both allocating a related field’s physical storage and for online formatting and data validation. The number of characters in an edit mask define the storage requirements. Constant and placeholder mask characters define format and validation requirements:

·     A constant mask character, such as a “/” or a “-” in a phone number edit mask, automatically displays for any field painted on an image in an APPX process.

·     Placeholder characters represent data-specific field positions. The individual placeholder character determines the allowable values for that position in an edit mask. For example, a “@” followed by a “#” in an edit mask indicates that the user must enter a letter followed by a number.

In addition, masks for some domains include reserved characters that affect the way APPX treats other mask characters, but do not relate directly to positions in the field value. For example, quotation marks in a date/time mask define mask text, but do not themselves display on an image. For more information, see the section on the date/time display mask in Chapter 3-14 or 3-15.

APPX Application Design Manual (01/13/03)

© 2003 by APPX Software, Inc. All rights reserved