> Nah. One of the most common uses of null is to communicate missing values in the sense of "this entity has this attribute but we don't know what its value is"

> Nah. One of the most common uses of null is to communicate missing values in the sense of "this entity has this attribute but we don't know what its value is". This is a fundamental feature needed in data management. I rarely use nulls like that. And then only for things outside of SQL databases like lazy loading or caching. And even then I still prefer null == null to be true. If nulls are for what you have written then why we are calling them "null" - no value? Why not calling them "unknown". Even then what is benefit in introducing non boolean logic to a relational query language? I have never seen anyone using any of three-valued logic benefits when writing SQL. Every time I get unknown logical value it means I have made a mistake in my query, which would be better handled by rising an error.