When writing DDL in SQL, you can specify a couple of constraints on columns, like NOT NULL or DEFAULT constraints. Some people might wonder, if the two constraints are actually redundant, i.e. is it still necessary to specify a NOT NULL constraint, if there is already a DEFAULT clause? The answer is: Yes! Yes, you … Continue reading Have You Ever Wondered About the Difference Between NOT NULL and DEFAULT?
Tag: not null
What if every object was an array? No more NullPointerExceptions!
To NULL or not to NULL? Programming language designers inevitably have to decide whether they support NULLs or not. And they've proven to have a hard time getting this right. NULL is not intuitive in any language, because NULL is an axiom of that language, not a rule that can be derived from lower-level axioms. … Continue reading What if every object was an array? No more NullPointerExceptions!