Updating database tables from xml
If you need to retain an exact textual copy, use large object storage.
But the rest of the time, you should consider the XML data type.
For example, the type information enforces more precise semantics on the XML values.
In addition, storage and queries are better optimized than on an untyped column.
You can, of course, specify the nullability or other column properties, but XML is all you need to include to create an XML column.
column is untyped XML, the inserted data did not have to conform to a specific schema collection; however, the data still had to conform to the ISO standards that govern XML.
In addition, the XML data type lets you store data that follows a structure too fluid and complex to fit easily into a relational model.
The same goes for XML files that you want to preserve in their original form, such as legal documents.The XML data type, introduced in SQL Server 2005, is a powerful construct.When used wisely, it can provide useful extensions to SQL Server. On the surface, it might seem like your run-of-the-mill type, except, of course, being geared toward XML data; but the ways in which it’s used, how its data is queried, and when and how XML columns should be indexed quickly sets the type apart from the rest of the crowd.For this reason, functions will be covered in a later article, after those XML components have been discussed.When you assign the XML data type to a column, variable, or parameter, you can optionally associate an XML schema collection with the object, thus ensuring that data within that object conforms to schema specifications. An XML object with no associated schema collection is considered untyped.