The
XML data type is used to store XML documents and fragments in a SQL Server
database. You can create columns and variables of the XML type and store XML instances in them.
XML
Data Type Methods
There are various methods that are as follows:
1.
Query()
2.
Value()
3. Exist()
4. Modify()
5. Nodes()
Limitations
of XML Data Type
1.
The stored representation of xml
data type instances cannot exceed 2 GB.
2·
It cannot be used as a subtype of a sql_variant instance.
3·
It does not support casting or converting to
either text or ntext. Use varchar(max) or nvarchar(max)
instead.
4.
It cannot be compared or sorted. This means an xml data type cannot be used in a GROUP BY statement.
5·
It cannot be used as a parameter to any scalar,
built-in functions other than ISNULL, COALESCE, and DATALENGTH.
6· It cannot be used as a key column in an index.
However, it can be included as data in a clustered index or explicitly added to
a nonclustered index by using the INCLUDE keyword when the nonclustered index
is created.