von Uwe Ricken | Nov 25, 2024 | DB Engine, SQL Blog
When revising one of my popular sessions on scenarios in which indexes no longer help, one of the topics covered was foreign key constraints for data integrity and JOIN eliminiation. During my research, I came across various arguments from developers who reject...
von Uwe Ricken | Nov 24, 2024 | SQL Blog
Although an index should provide a fast query, Microsoft SQL Server either does not want to use that index at all or does not want to use it optimally. The cause is not SQL Server or the index but think about the correct data types for your predicates in your queries!...
von Uwe Ricken | Nov 22, 2024 | SQL Blog
Database developers like to use the ISNULL() function to check two conditions and compare them with a search value. This is often done with the intention of finding records that do not have a value stored in the attribute. Sometimes they can get lucky – but not...
von Uwe Ricken | Nov 20, 2024 | DB Engine, Optimierung, SQL Blog, Tipps und Tricks
Unit tests/demos in workshops and conference sessions sometimes require a random key value from an existing table. In this article I present a solution that accomplishes this task quickly and in a resource-efficient manner. Why an existing – random – key?...
von Uwe Ricken | Okt 27, 2024 | SQL Blog
Sie gehen ins Internet und immer wieder stoßen Sie auf Blogartikel, Posts in Social Media und Kommentare, die Ihnen erzählen, dass Partitionierung Abfragen optimieren, weil sie nicht alle Daten lesen müssen. Fakt ist „Partitioning will NOT improve the...
von Uwe Ricken | Sep 26, 2024 | DB Engine, Indexierung, Optimierung, SQL Blog
Wer berechnete Attribute in Tabellen verwendet, sollte sich darüber im Klaren sein, dass unter bestimmten Voraussetzungen die Performance leidet. Dieser Artikel beschreibt die Nachteile, die sich aus „berechneten Attributen“ in Tabellenobjekten ergeben....
