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Category: Error Handling

Failure Tracking in SSIS

Published 2026-02-26 by Kevin Feasel

Andy Brownsword keeps a log:

SSIS packages provide great flexibility for integration between systems, but when they go wrong you can end up digging through logs or reports because every package logs differently. A standarised framework for tracking failures can drastically cut down troubleshooting time.

I reminisced recently about old code, I said “it’s not enough to make it work correctly. It needs to fail correctly too”. So in this post we’ll demonstrate a simple way to consistently track errors and failures in packages to help make troubleshooting much easier.

My recollection is that this kind of failure logging is less important if you have the SSISDB catalog, as it collects a lot of the information as well. But then again, I haven’t really used SSIS in a while, so that memory could be fuzzy.

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An Edge Case with Row Locks and Joins in PostgreSQL

Published 2026-02-25 by Kevin Feasel

Haki Benita digs into a problem:

Here’s a database riddle: you have two tables with data connected by a foreign key. The foreign key field is set as not null and the constraint is valid and enforced. You execute a query that joins these two tables and you get no results! How is that possible? We thought it wasn’t possible, but a recent incident revealed an edge case we never thought about.

If you answered “READ COMMITTED isolation level is weird,” congratulations: you win a prize.

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Modifying an Azure SQL Database with Mirroring to Fabric Enabled

Published 2026-02-12 by Kevin Feasel

Olivier Van Steenlandt runs into an issue:

Over the past few weeks, I have been doing some experimenting with Azure SQL mirroring to Microsoft Fabric. In the process, I ran into a couple of issues and challenges. In this data recipe, I will be going through one of my challenges when I got Azure SQL mirroring to Microsoft Fabric setup and running.

At first, everything seemed to be working as expected, and the integration felt very smooth. At that point, I continued to develop my test database in Azure SQL to learn a bit more about mirroring. I made a couple of minor changes to my test database and tried to publish them from my SQL Database Project.

Read on for the issue, as well as the solution—that is, assuming you don’t actually want to change any of the things you’re actively moving over into Fabric.

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Coding against the Happy Path

Published 2026-02-11 by Kevin Feasel

Andy Brownsword thinks about successful code:

A common time to revisit old code is when something breaks. I was contemplating Pat’s question this week when a field length change had caused a truncation issue in an old SSIS data flow. Some code doesn’t age badly because it’s wrong, but because it didn’t expect to fail.

It’s all too easy to write a piece of code which ‘does the thing’, run a few variant tests, and send it on its way. But will it stand the test of time? That’s where my good and bad code diverge, and I usually revisit the code and find the old milk.

Admittedly, I’m not as good at this as I should be either. It can be a challenge to think through the possible issues that could arise and develop code to mitigate or eliminate those issues. But as Andy points out, it can be critical to success.

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Investigating Full-Text Index Issues in SQL Server

Published 2026-02-06 by Kevin Feasel

Rich Benner doesn’t consider “remove the index” a valid solution:

The client noticed the D (data) drive was running out of free space and they asked us to investigate. We found that the SQL Logs folder was much larger than we’d expect. A considerable amount of this data was not database files (.mdf, .ldf, .ndf), but rather log files (.log and anything with a .Number file extension):

Read on for a bit of a shaggy dog story, as most IT stories tend to be. You start with one problem (almost out of disk space) and it turns into a cascading series of problems, so that by the end of things, you’re trying to figure out how to diagnose an error message when installing Node 16 on a Windows 7 laptop.

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NOWAIT Hints and Annoyances with Query Store Hints and Plan Guides

Published 2026-02-04 by Kevin Feasel

Erik Darling performs a rather late Airing of Grievances:

In this video, I delve into some of the frustrations and annoyances associated with query store hints and plan guides in SQL Server. I explore how these tools can sometimes hinder rather than help, particularly when trying to override certain behaviors or improve performance. For instance, I demonstrate the quirks of using a `NO_WAIT` hint in a transactional context and highlight why Query Store’s inability to support table hints is such a significant limitation. Additionally, I discuss the cumbersome nature of plan guides, especially their requirement for maintaining semantic affecting hints that might be detrimental to query performance. These issues underscore the need for more robust and flexible tools within SQL Server to better meet the diverse needs of database administrators and developers.

Click through for the video.

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LOB Data and Replication in SQL Server

Published 2026-01-23 by Kevin Feasel

Mark Beaumont diagnoses an error:

Recently, one of our clients encountered an issue while running a data update in SQL Server. The operation failed immediately with a configuration error, specifically targeting Large Object (LOB) data:

Length of LOB data (169,494) to be replicated exceeds configured maximum 65,536. Use the stored procedure sp_configure to increase the configured maximum value for max text repl size option, which defaults to 65,536. A configured value of -1 indicates no limit, other than the limit imposed by the data type.

The tricky part was, that client wasn’t using replication. Read on to learn about the culprit.

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Dealing with a Full Transaction Log

Published 2026-01-16 by Kevin Feasel

Rebecca Lewis performs some troubleshooting:

It’s 2am. Your phone wakes you. Rub your eyes, check your email, and there it is:

Error: 9002, Severity: 17, State: 4
The transaction log for database 'trading' is full due to 'LOG_BACKUP'.

The database is still online. Looks ok. You can read from it. But every INSERT, UPDATE, and DELETE fails. Production night-trading is effectively down.

The good news: It’s fixable — but, that fix depends entirely on what’s preventing log truncation.

Click through for a choose-your-own-adventure story.

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Lessons Learned in a SQL Server 2025 Upgrade

Published 2026-01-15 by Kevin Feasel

Aaron Bertrand shares some lessons learned:

We recently upgraded multiple systems to SQL Server 2025. The engine upgrade itself was smooth, but three unexpected issues surfaced in our lower environments as we planned out production. None of these issues prevented the upgrade from completing, but all three could easily derail an otherwise smooth in-place upgrade to SQL Server 2025. What were these issues, and how can you avoid hitting them?

My biggest surprise out of this is that full-text search actually got upgraded.

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