Скачать или смотреть How to Retrieve Descriptor Values from XML in SQL Server 2019

Learn how to efficiently extract descriptor values from XML data in SQL Server 2019 using XPath. Follow our clear, step-by-step guide!
---
This video is based on the question https://stackoverflow.com/q/77399423/ asked by the user 'olorin' ( https://stackoverflow.com/u/4096913/ ) and on the answer https://stackoverflow.com/a/77399516/ provided by the user 'Yitzhak Khabinsky' ( https://stackoverflow.com/u/1932311/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Get value of Descriptor from XML

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Introduction

Working with XML data in SQL Server can be challenging, especially when trying to extract specific attributes from your XML documents. One common problem arises when you need to retrieve values from nested elements, such as the Descriptor attribute found in <wd:Job_Posting_Title>. In this post, we’ll explore how to effectively get these values from your XML data stored in SQL Server 2019.

The Problem

You might find yourself in a scenario where you have a SQL table containing an XML column. You want to extract several details, such as job posting titles and their corresponding descriptors, but your current SQL query is not retrieving the descriptor value as expected. Instead, it returns NULL for the descriptor. This can be frustrating, especially when the data is essential for your analysis.

Understanding the XML Structure

Before we dive into the solution, it’s crucial to understand the structure of the XML data you're working with. Here’s a simplified look at the XML data of a job posting:

[[See Video to Reveal this Text or Code Snippet]]

In this structure, the Descriptor attribute is located within the wd:Job_Posting_Title element, which you need to access efficiently using XPath.

The Solution

Step 1: Declare the Default Namespace

One effective way to simplify XPath expressions is by declaring a DEFAULT namespace in your SQL query. This approach allows you to reference elements without specifying the namespace prefix repeatedly.

Step 2: Write the Query

Here’s a revised SQL query to extract the desired values:

[[See Video to Reveal this Text or Code Snippet]]

Step 3: Review the Output

When you run the revised query, you should expect to receive the following output, including the previously elusive descriptor value:

WIDJob_Requisition_IDJob_Posting_Title_DescriptorDate_Request_Enteredec98bef15bdd01d48e622807e4244918JR01JR01 Program Wholesaler2021-04-18-07:00Conclusion

Retrieving values from XML in SQL Server can be tricky, but with proper understanding of XML structure and efficient use of XPath, you can streamline your queries for better results. By declaring a default namespace and utilizing precise XPath expressions, you can easily access attributes like descriptors and improve your data extraction process. We hope this guide assists you in overcoming any challenges you may face while working with XML data in SQL Server.