curretnly all values which evaluate to false will turn up missing after json_serialize
values should only be missing iff they are really empty "" instread the following will also be missing: NOTFOUND 0 NO "" etc....
Maybe a undefined value should be introduced (or NOTFOUND should a special meaning) that way "" would also be serialized
curretnly all values which evaluate to false will turn up missing after json_serialize values should only be missing iff they are really empty "" instread the following will also be missing: NOTFOUND 0 NO "" etc....
Maybe a undefined value should be introduced (or NOTFOUND should a special meaning) that way "" would also be serialized