Patterns for Identifiers
Identifiers are all around us. Social Security numbers, zip codes, and DUNS numbers (unique numbers issued by Dun & Bradstreet and used to identify business entities) are just a few. The range of values of such things is usually way too large and dynamic to practically enumerate in a schema, although business applications usually validate them in their databases. Even though we might not want to enumerate the set of allowable values, we can do a level of validation by specifying a pattern to which the identifier must conform. For example, U.S. Social Security numbers have the general pattern NNN-NN-NNNN, where N represents a digit from 0 through 9. U.S. zip codes (in the five-digit form) have a pattern of NNNNN. The common ...
Get Using XML with Legacy Business Applications now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
