Gullible about Nullable – Stuff I thought I knew…and didn’t

Taking a break from the advanced mathematical theory required to work out all the permutations that will allow England to qualify from their group, I thought that, by way of light relief, I’d have a look at NULL in SQL.

I was recently disabused of a long-held notion that NULL will always evaluate to TRUE. I can’t remember for the life of me where I acquired this delusion. It’s never been particularly relevant to me as, whenever I’m likely to be faced with such a situation, I simply use the NVL function.

I’m wondering – is it just me – is that something I’ve mis-remembered from my days as an Oracle neophyte back when the world was young? Continue reading