Re: Quote of the Week

>> Yes, Fabian can be a pain, even to the point of sharp, unwarranted
words. <

I believe that he still holds second place for being kicked out of the most CompuServe forums. First place belongs to a lady with logorhea who would get off of her medication and would type insults to random people for days until she collapsed.

>> But his criticism of you is well founded AFAICG. <<

Actually, I don't think so. Here is why:

1. Someone send Chris Date one of my very old SQL puzzles and wanted help with it. Chris answered it with his personal programming language rather than Standard SQL. The problem involved displaying the hire date and last promotion date for each employee in a personnel. The specs were to use a NULL, if the employee was a new hire. Since Chris Date's version of the Relational Model does not have NULLs, he used an arbitrary dummy date instead and thus created false information.

I sent an email that discussed this problem and a new solution to dbdebunk.com which used the SQL-92 OUTER JOIN syntax that did not exist at the time of the original publication and a change in the table's DDL.

It was never acknowledged, much less printed.

2) I made a remark in one of my books that SQL cannot technically violate 1NF because all columns are scalar datatypes. That was followed by detailed remarks as to how programmers are so used to thinking in terms of arrays and lists that they "fake it" with various tricks (numbered column names, strings of Comma separated values, etc.)

The qualification was removed when I was quotes on dbdebunk, completely mis-representing my position. Then in a reply to an email on 1NF, Fabian made reference to the same kind of thinking!

3) He still advocates an adjacency model for trees. Unfortunately, he does not given all the constraints needed to assure that such a table is actually a tree and not a general graph, nor does he mention that you **must** use procedural code to manipulate that model. In short, it is the worst way to model a tree in a set-oriented language, but to give it up he would have to acknowledge either path enumeration or nested sets models, and that he missed it.

4) He supports Chris Date's temporal model, which advocates a chronon model for temporal data and some weird extensions to the relational model for them. Even before Rick Snodgrass did his work in the field, Zeno's paradoxes and Einstein's physics showed that time is a continuum and not a set of discrete points, so time is made up of durations that cannot be defined as countable sets of points.

5) If anyone mentions my name to him, he will simply insult me without giving them a reason. Example: on dbdebunk.com,one of his replies to an email that mentioned my name as a source for SQL info was simply "Stay away from Celko!" and nothing else.

At least, I itemize differences in the SQL-92 (me), Chris Date and Ted Codd versions of the RM and the various extensions to each one. Received on Thu May 13 2004 - 06:47:45 CEST