3 ms·

Thanks for the explanation, I forgot that null != null in databases. I was thinking more about how null != 0 and is a separate concept in languages with optiona

Thanks for the explanation, I forgot that null != null in databases. I was thinking more about how null != 0 and is a separate concept in languages with optional values. You’re right that optionals in these languages don’t quite work the same as in databases

Sniffnoy 6y ago
But it's not NULL != NULL. It's that NULL == NULL is NULL. That's different! NUll != NULL is also NULL, for instance.
- vivekseth 6y ago
  Maybe a concise way to describe it is that in databases NULL represents the absence of a value. Since NULL is not a value, operators like == and != don't really make sense on NULL, and also produce NULL as an output.