XML documents are widely used in various applications and industries. In SQL Server, you can store and manipulate XML data using the XML data type and XQuery language. In this article, we will explore the concept of modifying XML documents in SQL Server.

There are several scenarios where you might need to modify XML documents. This can include deleting elements and attributes, inserting new elements, modifying existing elements, and re-structuring the XML document. We will cover some of these scenarios in this article.

Deleting Elements and Attributes

Let’s start with deleting elements and attributes from XML documents. The syntax to perform these modifications is similar, but it can be confusing for many people. To make it less confusing, we will cover elements and attributes separately.

Here is an example of deleting an attribute from an XML document:

DECLARE @x XML
SELECT @x = '
<Employees>
  <Employee name="Jacob" city="NY" Team="SQL Server"/>
  <Employee name="Steve" city="FL" Team="SQL Server"/>
  <Employee name="Bob" city="CA" Team="ASP.NET"/>
</Employees>'

SET @x.modify('
    delete (Employees/Employee/@Team)[2]
')

SELECT @x

This example deletes the “Team” attribute from the second “Employee” element. You can also delete attributes based on their position or specific values.

Deleting Elements and Attributes by Position

You can delete elements and attributes based on their position using the position() function. Here is an example:

DECLARE @x XML
SELECT @x = '
<Employees>
  <Employee name="Jacob" city="NY" Team="SQL Server"/>
  <Employee name="Steve" city="FL" Team="SQL Server"/>
  <Employee name="Bob" city="CA" Team="ASP.NET"/>
</Employees>'

SET @x.modify('
    delete (Employees/Employee[position()=2]/@Team)
')

SELECT @x

This example deletes the “Team” attribute from the second “Employee” element using the position() function.

Deleting Elements and Attributes by Value

You can also delete elements and attributes based on their values. Here is an example:

DECLARE @x XML
SELECT @x = '
<Employees>
  <Employee name="Jacob" city="NY" Team="SQL Server"/>
  <Employee name="Steve" city="FL" Team="SQL Server"/>
  <Employee name="Bob" city="CA" Team="ASP.NET"/>
</Employees>'

SET @x.modify('
    delete (Employees/Employee/@Team[.="SQL Server"])
')

SELECT @x

This example deletes the “Team” attribute from all elements where the value of the attribute is “SQL Server”.

Conclusion

In this article, we have covered various scenarios of modifying XML documents in SQL Server. We have seen examples of deleting elements and attributes based on their position and value. These modifications can be performed using the modify() method of the XML data type.

XML manipulation in SQL Server provides a powerful way to work with XML data. It allows you to easily modify and transform XML documents to meet your specific requirements.

If you have any additional scenarios or questions related to modifying XML documents in SQL Server, feel free to reach out to us. We are here to help!

Author: Jacob Sebastian