Joe Celko is one of the most widely read of all writers about SQL, and was the winner of the DBMS Magazine Reader's Choice Award four consecutive years. He is an independent consultant living in Austin, TX. He has taught SQL in the US, UK, the Nordic countries, South America and Africa.
He served 10 years on ANSI/ISO SQL Standards Committee and contributed to the SQL-89 and SQL-92 Standards.
He has written over 800 columns in the computer trade and academic press, mostly dealing with data and databases. He is the author of eight books on SQL for Morgan-Kaufmann, including the best selling SQL FOR SMARTIES.
Joe is a well-known figure on Newsgroups and Forums, and he is famous for his his dry wit. He is also interested in Science Fiction.
In the first part of this series on Temporal Data, Joe explained how it is that the Common Era calendar is irregular and mentioned that, although there are ANSI/ISO Standards for temporal operations in SQL, every vendor has something different. Now, he discusses other factors to take into account when using temporal data such as Holidays, and discusses a few techniques using Calendar, Report Usage and History tables… Read more
In the first of a series of articles on the tricks of tackling temporal data in SQL, Joe Celko discusses SQL's temporal data types and agonizes over the fact that, although there are ANSI/ISO Standards for temporal operations in SQL, every vendor has something different. He explains the mysteries of such things as time-zones, lawful time, UTC, CUT, GMT, CE, DST, and EST.… Read more
You'd have thought that a unique constraint was an easy concept - Not a bit of it; it can cause a lot of subtle problems in database designs. Joe Celko goes over the ground of unique keys, primary Keys, foreign keys and constraints.… Read more
In his first article for Simple-Talk, Joe Celko demystifies the use of Constraints, and points out that they are an intrinsic part of SQL and are a great way of ensuring that a business rule is done one way, one place, one time. Almost all database programmers will find something new and useful in this article.… Read more