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Category: T-SQL Tuesday

HTML Parsing in T-SQL

Published 2025-10-22 by Kevin Feasel

Louis Davidson goes looking for list items:

From the title of “Favorite String Parsing”, I will say 100% it is using SQL Server 2025’s addition of Regular Expressions. Previously, parsing text in SQL Server was one of my least favorite things to do. Regular expressions will make it just a bit nicer, because it has a lot more power than SUBSTRING, LEFT, RIGHT, and CHARINDEX/PATINDEX. All generally “good enough” functions for a lot of the things you need to do, but often woefully inadequate for parsing large amounts of text.

Yeah, T-SQL RegEx is definitely a nicer approach, though HTML doesn’t have to follow the consistency rules of XML due to browsers being very forgiving in their interpretation of the language, so it’s easy to get tangled up trying to parse websites.

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String Parsing in T-SQL

Published 2025-10-21 by Kevin Feasel

Rob Farley shares some thoughts:

But let’s talk about non-regex methods for parsing strings and the patterns that I use. I find that the biggest issue with most string parsing is complexity. Even something as simple as finding the value between the 2nd and 3rd hyphens can be done in different ways with different levels of complexity, and even if it works, maintaining that code can become really hard.

For example, finding the position of the first hyphen might be as simple as using the CHARINDEX function. Finding the second might involve two CHARINDEX functions, and calling SUBSTRING with parameters that have increasingly nested CHARINDEX calls… well, you can see how the complexity quickly builds

Rob digs into one of my favorite use cases for the APPLY operator: simplifying calculations, or in this case simplifying expression chains. Granted, I have also grown to appreciate the DuckDB solution of allowing for function chaining. The demo examples in that documentation are limited but you can do things like goose_name.lower().replace('goose', 'duck').replace(' ', '') and it will work fine.

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T-SQL Tuesday 189 Round-Up

Published 2025-08-20 by Kevin Feasel

Taiob Ali summarizes this month’s T-SQL Tuesday:

I would like to thank all the participants of T-SQL Tuesday #189. If I missed your post, it was not intentional. Please let me know, and I will add it to this list.

I am proud of this community and feel lucky to be a small part of it. I admire everyone who joined the blog party and shared their thoughts on how AI is changing our careers, as well as your thoughts on AI tools.

Click through to see the responses.

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Troubleshooting Weird Issues

Published 2025-06-11 by Kevin Feasel

Chad Callihan says sometimes, the best answer is not to play the game:

After some database infrastructure changes related to phasing out the use of linked servers, I encountered issues with a setup tool used to build out new databases and other related features. One section of the tool was failing, and the errors indicated that there were still stored procedures utilizing linked servers, which was causing the problem. I asked myself a few questions on how best to proceed. Does the setup tool need to be updated? Do the related database procedures using linked servers need to be updated? Do the linked server changes made need to be rolled back altogether?

Read on for a proper Gordian Knot solution.

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Troubleshooting with Extended Events

Published 2025-06-11 by Kevin Feasel

Grant Fritchey knows one way to solve the problem:

A client asked us to tell them when a query ran long. Simple. We have a long running query alert, all built in to Redgate Monitor, so, done. No, see, we like getting alerted when queries run long, but not really long, plus we’re more concerned with just one database.

Click through for the story and how Grant was able to help out the client. Also, read the comments for an entry by Special Guest Star Erik Darling.

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Databases and Reboots

Published 2025-06-10 by Kevin Feasel

Rob Douglas will reboot many things, but not the database server:

I am taking a slightly different tangent. My problem is neither strange or unique – in fact it’s infuriatingly common and it stems from one of the most common troubleshooting techniques in IT. While asking users “Have you tried turning it off and on again?” is a common go to for tech support call handlers, it is not a great idea when the “it” you are talking about is a database server

Click through for a cautionary tale, as well as an explanation of why this usually isn’t the smart play.

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