Category: sql server

Tea with Kalen! An interview with Kalen Delaney (#DBAsAtMidnight)

We had an AMAZING talk with Kalen Delaney – wait, you do know who Kalen is, don’t you? Rightfully, @SQLQueen on Twitter. Over 30 years in SQL Server. Independent trainer and consultant. Author of the SQL Server Internals series of books, among others. Runs https://www.sqlserverinternals.com/ Trekkie. All-around awesome person. In our ramblings, we covered college, food, linguistics, career, and of […]

Fix WHERE clause AND/OR/NOT confusion with truth tables

The ANDs, ORs, and NOTs in a T-SQL query’s WHERE clause can get confusing, especially if you’re thinking of it like plain-Jane algebra. Here I show you how to figure out exactly what a query is doing, using truth tables!