von Uwe Ricken | Dez. 21, 2024 | 300, DB Engine, SQL Blog, Statistiken
This week I was called out twice to an incident at a customer’s site where a massive blocking problem occurred in the web shop. The root cause was the AUTO_UPDATE STATISTICS option. One blog article is not enough to explain the complexity of this problem....
von Uwe Ricken | Dez. 20, 2024 | Administration, Informationen, SQL Blog, Statistiken
In customer meetings, I am often asked about the formula that Microsoft SQL Server uses to automatically update statistics. I always have to look it up myself because this formula depends on a number of factors. For this reason, I decided to develop my own...
von Uwe Ricken | Dez. 16, 2024 | SQL Blog
Partitioning is, among other things, a great feature when it comes to storing new data in the table as quickly as possible. The locking behavior for the table in particular is a decisive advantage of concurrency when using LOCK_ESCALATION = AUTO. There are a few...
von Uwe Ricken | Dez. 12, 2024 | Administration, Allgemein, SQL Blog
You often read on social networks that a DBA’s job is to optimize databases, among other things. I think that’s a misinterpretation of the – important – role of a DBA. Why? I’m happy to share my opinion on the role a DBA has to play in a...
von Uwe Ricken | Dez. 9, 2024 | 200, DB Engine, SQL Blog
JOIN Elimination in Microsoft SQL Server is an optimization technique with foreign key constraints where the query engine removes redundant JOIN operations during query execution. This occurs when the data from the joined table is not used in the SELECT clause or any...
von Uwe Ricken | Dez. 1, 2024 | DB Engine, Optimierung, SQL Blog
My first article on using foreign key constraints in databases included the claim that using them slows down an application. This article addresses the claim that a Foreign Key Constraint use locks and can cause Deadlocks and thus slow down applications. Claim Foreign...