A Fine Slice Of SQL Server
Deb Melkin deals with disaster:
One morning, the help desk support person came over and said this one client was having performance issues. This was one of the cases where we would just reboot. It was early and there would be plenty of time for everything to be back up and running before the system was needed. So I gave the go ahead to reboot the server.
This did not go well. Read on for the rest of the story.
Leave a CommentA buddy of mine invited me to take a road trip and join him in Philadelphia, PA to take a tour of the USS New Jersey while she was in drydock for its required museum ship maintenance. Quite possibly a once in a lifetime opportunity – we wouldn’t be touring the inside of the ship, we would be walking around underneath her, on the floor of the drydock. I hit the road on Friday, and picked him up at the airport. We got dinner, unwound from our respective travels, and planned out the following day.
Click through to see what happened next.
Leave a CommentAndy Brownsword tells his origin story:
I enjoy a good war story.
But no, this isn’t the time Azure blindsided me, when service accounts were locked, or when I left a transaction open and halted a production system (easily fixed by closing SSMS 😅). Mine is a pivotal personal moment.
Andy humbly leaves out the part where he was hand-to-hand kung fu fighting a series of ninjas while doing all of this, but you can just assume that in there.
Leave a CommentAlexander Arvidsson tells a story:
The patient was a misbehaving SQL Server 2014 running in a two-node cluster. It was your garden-variety cluster with a shared disk and a remote witness. In my experience, as long as the customer has enough know-how to maintain a cluster like this, it’s essentially bulletproof.
This specific cluster was not.
Click through for the story, as well as a reminder of why people in mission-critical situations tend to follow checklists and say the items aloud.
Leave a CommentReitse Eskens troubleshoots an error:
I’ve declared a variable and assigned it a value. Now, I want to check if my variable matches the regular pattern of Dutch postal codes. These codes are four numbers followed by two letters. Using a regular expression helps check validity.
My expectation was that this query would return either 1 or TRUE. In any case, a result telling me that the postal code is valid. Instead, it throws an ‘Incorrect syntax error near the keyword ‘REGEXP_LIKE’.
Click through for the screenshot and the explanation.
Leave a CommentDualcore DBA violates Betteridge’s Law of Headlines:
I recently had cause to reseed an identity column on a table in SQL Server, which got me wondering “If we reseed an identity column to a value lower than the existing identity values in the column, could it cause a clash?” Because why wouldn’t you wonder if you can cause something to break, whilst performing a fairly simple task!?
Let’s find out what happens…
Click through for the demonstration.
Leave a CommentLouis Davidson bangs his head against a wall:
When we decided to use T-SQL and a Fabric Data Warehouse for our ETL, I started thinking about generating the code with the metadata in the system catalog views or the
INFORMATION_SCHEMA. Having done this sort of thing before in SQL Server over the years, it seemed really straightforward. And it kind of is, until it isn’t.In this blog I want to show you a few ways you need to understand how working with metadata and temp tables varies (sometimes wildly) from the comfortable SQL Server environment and language you know very well, and give tips on how to get around these differences.
Click through for some of the fun you can have with a distributed SQL Server-like product.
Leave a CommentJordan Boich troubleshoots an issue:
SQL Server won’t start and at first, I couldn’t figure out why. When I logged off for the day on Friday, everything was happy, but when I logged on Monday morning, a heavily used test instance of SQL was not running and wouldn’t start.
Quick side note, and it’s funny looking back on now, but in the moment it sucks. You ever have to start the SQL Server Service from Configuration Manager, and when you right click -> Start, or right click -> Restart you see that green progress bar start to go and under normal healthy circumstances, it probably gets a third of the way through before SQL kicks over. But when you start to see that progress bar start to make more and more progress, you know before it even fails on you that something isn’t going to work right. You start to get that sinking feeling in your stomach. That was me.
Click through for the troubleshooting process as well as the end result.
Comments closedChris Webb diagnoses a case of passive voice:
A few months ago I wrote about a rare error – the “Maximum allowable memory allocation” error – that may occur when the physical machine, or node, that a semantic model is running on in the Power BI Service comes under memory pressure. Recently, someone I was working with who was doing some load testing showed me a related error:
The operation was canceled and the database was evicted to balance the CPU load on the node. Please try again later.
Read on to see what causes this.
Comments closedSean Gallardy troubleshoots an error:
This used to be a very hot topic around SQL Server 2016 when automatic seeding first came out, then everyone learned how automatic seeding was just manual seeding but done for you and the topic went away. A decade later, it’s somehow back to being a hot topic. I guess all that is old is new again.
Error 1408 states that the database doesn’t have enough log to find a starting point with the primary/principal – which, let’s just use AG terminology from this point on because mirroring has been dead for 14 years and counting.
Mirroring has been dead and yet it lives on in undead form. Regardless of that, Sean provides some good information around what automatic seeding actually means and what you can do if you get stuck with Error 1408.
Comments closed