The Perils of Querying SQL Server Replicas Under Load

Last week at Stack Overflow we had an internal hack-a-thon, or as we call it, a make-a-thon. I was on the bug-bashing team, which is the team that attempts to fix smallish bugs we haven’t gotten around to fixing, due to other time-constraints. I was tagged to investigate a bug about duplicate badges being awarded because it looked to possibly be an easy fix in SQL. At first glance it looked simple enough, but once I started digging in, I figured out very quickly it wouldn’t be.

T-SQL Tuesday #122 - Impostor Syndrome

This month’s T-SQL Tuesday is hosted by Jon Shaulis, who has asked that we talk about impostor syndrome. This subject is close to my heart, as I have dealt with it throughout my career. I didn’t study computer science or engineering in college. I never even took a computer class. I sort of just fell into working as a web developer because I had someone tell me they wouldn’t hire me due to lack of experience.

Hitting Parallel_Redo_Flow_Control waits with Availability Groups

In late June 2019, June 26th to be exact, we experienced an outage on Stack Overflow for about 11 minutes. It’s not unusual that we had an outage. They happen. Not often, but they do still happen. This one, however, was a little different because it was caused by a maintenance job that was running on our primary SQL Server for Stack Overflow. The job that caused it was something I’d noticed about a month prior, but had stopped it before an actual outage occurred.

Finally, My first PASS Summit

I’ve been working with SQL Server for a long time, and have always wanted to attend PASS. For one reason of another, with numerous employers, I hadn’t been able to go. The answer was always no. <insert sad face> The biggest blocker was always the cost. The conference is expensive. Seattle is expensive. It has always been impossible to get my employer to foot the bill for it. This year I was incredibly lucky that my employer, Stack Overflow, paid for my trip to PASS Summit.

How Stack Overflow upgraded from Windows Server 2012

Warning: This post is long. While working through this massive server upgrade/migration process, tears were shed, many cuss words were said, along with a general feeling of frustration, which ultimately culminated into extreme happiness once the migration was completed. The scale and complexity of the implementation factor into the length of this post, and I’ll share my thought process on how this was executed, so here goes. Last year, when we upgraded to SQL Server 2017 we didn’t make any changes to the operating system on our main production servers.