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XML (Extensible Markup Language) has become a prominent format for exchanging data between platforms. It is likely that at some point as a SQL Server developer, you might need to work with XML data as well. Here, we’ll explore how SQL Server allows you to incorporate XML data in your analysis, using SQL code.
Storing XML Data
SQL Server allows XML data to be stored in XML data type variables and columns. Here is a brief example of how to declare an XML variable and store XML data in it:
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DECLARE @myXml XML SET @myXml = ' <Customer> <FirstName>John</FirstName> <LastName>Doe</LastName> </Customer>' SELECT @myXml |
Running the above script in SQL Server would display the XML data stored in the @myXml variable.
Querying XML Data
SQL Server also allows you to query XML data using XQuery, an SQL-like language designed specifically for querying XML data. Here is an example of how to extract FirstName from the above XML:
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SELECT @myXml.value('(/Customer/FirstName)[1]', 'VARCHAR(50)') |
Running the above script in SQL Server would return ‘John’ – the value of the FirstName element.
Modifying XML Data
You can also modify XML data using the modify() function of SQL Server. Here is an example demonstrating how to change the first name of the customer from ‘John’ to ‘James’:
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SET @myXml.modify('replace value of (/Customer/FirstName/text())[1] with "James"') SELECT @myXml |
Running the above script in SQL Server would return the modified XML.
Conclusion
All these examples show that SQL Server provides a flexible environment for managing and manipulating XML data. While the XML capabilities in SQL Server may not eliminate the need for more specialized XML databases, they are quite robust and meet most standard XML processing requirements.