Formatting XML Output in SQL Server 2005: A Guide to FOR XML EXPLICIT

When working with SQL Server, you might encounter scenarios where you need to transform your query results into XML format. One common challenge arises when trying to achieve a specific XML structure. For instance, you may need to pass the output into another stored procedure while maintaining a certain format. In this blog post, we look at how to format XML output correctly in SQL Server 2005 using the FOR XML EXPLICIT clause.

The Problem: Desired XML Structure

Let’s start by analyzing the problem. Consider a table with a structure as illustrated below:

To pass the output as XML to another stored procedure, you need the XML format to look like this:

<root>
    <clientID>12345</clientID>
    <clientID>54321</clientID>
</root>

However, your initial attempt yielded this result:

<root clientID="10705"/>

Clearly, you are not getting the desired output. Let’s address this.

The Solution: SQL Query Breakdown

To achieve the desired XML format, you need to adjust your SQL query. Here’s a step-by-step guide to reaching the expected output.

Step 1: Modify the SQL Query

Your initial SQL query needs some tweaking. Replace it with the following statement:

SELECT
    1 AS Tag,
    0 AS Parent,
    AccountNumber AS [Root!1!AccountNumber!element]
FROM
    Location.LocationMDAccount
WHERE
    LocationID = 'long-guid-here'
FOR XML EXPLICIT

Step 2: Understanding the Query Components

• SELECT Statement: You start by selecting the desired data, in this case, AccountNumber.
• Tag and Parent: The Tag and Parent values are essential for correctly structuring the XML hierarchy. Here, 1 and 0 are used to signify the root level.
• XML Format Specification: The AS [Root!1!AccountNumber!element] is critical. It aims to generate XML elements for each AccountNumber.

Step 3: Executing the Query

Run the modified SQL query against your SQL Server database. If everything goes as planned, you should now receive the XML output structured correctly, looking like this:

<root>
    <AccountNumber>12345</AccountNumber>
    <AccountNumber>54321</AccountNumber>
</root>

Conclusion

Achieving the desired XML format can be straightforward with the right SQL queries. The FOR XML EXPLICIT clause in SQL Server 2005 allows for detailed control over how your data is transformed into XML. By adjusting your query to include the correct Tag, Parent, and formatting components, you can successfully format your XML output to meet your needs.

If you follow the steps outlined in this blog post, you should now be able to format your SQL Server 2005 output into the XML structure you need. Happy querying!