check (not (filetype = 'h' and target is null)),
check (target is null or length(target) between 1 and 4095),
check (hash is null or length(hash) between 1 and 1024),
check (not (filetype = 'h' and target is null)),
check (target is null or length(target) between 1 and 4095),
check (hash is null or length(hash) between 1 and 1024),