Why doesn MSXML support XML Schema (XSD) or, Why did Microsoft make their own version of schema (XDR)?
XML-Schema efforts are continuing, and as of this writing (12/5/2000), XML-Schema is not finalized. Microsoft has committed to support XML Schema when it becomes a full W3C recommendation. Before XML-Schema efforts began, a number of companies developed the XML-Data specification. When it became apparent that XML-Schema would supercede XML-Data, Microsoft wanted to support XML-Schema, but needed to ship product without waiting for standards efforts to continue. To this end, XML-Data Reduced was developed as a minimal subset of XML-Data that was guaranteed to be compatible with XSL-Schema as it developed. Current Microsoft XML parsers will validate documents against an XDR schema, and will support XSD when it is released. The released MSXML3 uses XDR, but beta products such as the .NET framework SDK are already using XSD. MSXML4 will use XSD. In addition, tools to automatically convert XDR to XSD are now provided. In fact, the conversion is accomplished through an XSLT stylesheet. If yo
