Yesterday I fell into a very simple but dangerous SQL trap. Can you identify it? Found it? It’s the comparison to null. My intention was to get rows where another_column was null, however the query did not do so. It didn’t give me any results where another_column was null, but didn’t give me any error either. Why? Null in SQL is not a real value. Null means “lack of a value” or “unknown”. Anything compared to null leads to an “unknown” result. Therefore, in SQL there are actually three values conditions can evaluate to: true, false, and unknown/null. This is called Continue Reading
programming
App Remote – Unleashing the Apple Remote
I’ve been using Sofa Control for my Apple Remote since I bought my Mac in 2009. I use Sofa Control pretty much every week when I volunteer with the youth ministry at my church. The Apple Remote by itself only works with certain programs that are designed to handle its input and it lacked support for other programs we were using such as OpenSong, which we use for song lyrics. So I bought a license for Sofa Control. Recently Sofa Control’s move to the App Store required all existing customers to repurchase the license. I didn’t want to shell out another Continue Reading