Much like CLR user-defined types (UDTs) XML is now a new first-class data type in SQL Server 2005. Developers may now be tempted to use this data type to avoid having to write code to "shred" XML data into tables (i.e. instead of using OPENXML to populate tables with the data).
Unfortunately, using the XML data type like this has many of the same problems as representing data in user-defined types. Developers should keep performance in mind, as querying a node of an XML column will require the engine to evaluate a separate XML query for each row of the table. Normalization issues are also present, similar to using CLR UDTs. Ensuring data integrity will be extremely difficult in databases that make too much use of the XML data type.
Do you have comments on this Ask the Expert Q&A? Let us know.
Dig Deeper on Microsoft SQL Server 2005
Related Q&A from Adam Machanic
Migrating to SQL Server 2005 from SQL Server 2000 is a hefty feat when compared to upgrading from 7.0 to SQL Server 2000. Site expert Adam Machanic ... Continue Reading
Multiple readers can sometimes read the same row simultaneously causing a false result. SQL Server 2005 expert Adam Machanic suggests modifying the ... Continue Reading
SQL Server 2005 and T-SQL do have differences. The advantages and disadvantages would depend user environment as described by SQL Server 2005 expert... Continue Reading
Have a question for an expert?
Please add a title for your question
Get answers from a TechTarget expert on whatever's puzzling you.