Sum types like Option/Maybe (or C's NULL) don't do the same thing as SQL's NULL, though. By all means, if you don't need NULLs, then don't use them — `NOT NULL`

Sum types like Option/Maybe (or C's NULL) don't do the same thing as SQL's NULL, though. By all means, if you don't need NULLs, then don't use them — `NOT NULL` should probably have been the default in table statements — but they serve a purpose.