Writing Good XML Schema
One of the biggest hurdles for XML schemas is the learning curve. An XML schema is not easy to write; a good XML schema is even less easy. A good schema takes into account all boundary conditions just like a good programXML schemas are incredibly precise; they are also verbose. This should come as no surprise to anyone who interacts frequently with the equally wordy plain XML, the foundation for XML schemas.
There is a noticeable amount of overhead to using XML. The XML verboseness just mentioned translates directly into extra overhead for deciphering XML. Understanding XML requires a full parser
A native programming
struct
ure such as a C struct or a Java class is much more efficient. XML validates against an XML schema. This validation is time consuming. Worse, loading an XML schema document also requires parsing XML
As computers get faster and faster, developers tend to ignore the effort required from a processor. Of course, in some cases, the programmer can cache schema information for speed. Even so, a user might perceive the time delay caused by a single validation. Almost certainly, the amount of time required for multiple validations has the potential to annoy users
