30 November 2010
29 November quiz: interesting reactions to a "tricky" quiz (1706)
The 29 November quiz, the first authored by Ken Holmslykke, one of my invaluable quiz reviewers elicited several interesting reactions. It was a tricky quiz, no doubt about that. Involving implicit conversions and comparisons of string values, it was a hard one to sort out. I received the following two observations from players: 1. This is not an objection to the quiz at all (I did get i right , this is more a slight concern about "question styles..." Three cheers for Ken (nice guy taking some of the load off Stevens shoulders. But his "question style" is somewhat different. The thing is, that the "topic" of the question mostly is what happens with the implicit conversions of numbers to strings. But the use of all_objects.object_type%TYPE in my opinion mostly serves to confuse the reader so he won't recognize what the question is really about. Had the subtype index_t been declared as VARCHAR2, the question would have been clearer, that the subject was to test the readers knowledge of how a string associative array works if you use numbers working with that array. So just a slight warning (mostly to Ken) not to try to be too much "clever" when formulating questions. PL/SQL Challenge is mostly about learning, which to me means that it should be reasonably clear what topic the questions are trying to test our knowledge about. This tricky "obscuring" of the question topic is not (IMHO) consistent with the normal "question style" of Steven. That said, I do believe it will in the long run be a good thing to have questions from different authors, who might have a different angle than Steven Just my 2 bits. 2. It's a first time when I really want to nominate this question as a "Question of Year" (or at least a Quarter). I choose a wrong option, but I don't regret. It took a while for me to explain this right option. The only concern I have is about NLS_SORT / NLS_COMP parameters. People will definitely raise this point up, because you even may create your own character set definition and specify a different sort order using those parameters. I hope it's hard to achieve it and and question will be left unmodified. Regarding #1, ironically, though Ken wrote the original quiz, I did some editing and I am the one who introduced the use of the subtype. Ken originally declared the type as VARCHAR2. So I must take the "blame" for that obfuscation. Regarding #2, we document in the assumptions a default installation of an Oracle instance with a specific character set. Is that not enough to cover the issue raised regarding NLS_SORT and NLS_COMP? We'd love to hear what you thought of the quiz.