The Difference Between Rollup and Cube

Learn about the fundamental differences between the ROLLUP and CUBE operators.

Simple SQL: Handling Location Datatypes

How do you record locations in SQL? Most relational database systems support spatial and geographical data, generally using the round-earth system based on the SQL specification of the Open Geospatial Consortium (OGC). However, this is not the only approach, as Joe Celko explains.

The Nonsensical Count

Game Day Planning

Tally Tables and Table Variables

More Precedence

Default variable assignment

Simple SQL: Random Thoughts

How does one get a truly random sample of data of a certain size from a SQL Server database table. Well, there are simple non-portable tricks one can use, such as the NewID() function, but then refining those can be tricky. Take the Rand() function for a start. Can it really provide you with a truly random number? Why doesn't the TABLESAMPLE clause give you a set number of rows? Joe Celko scratches his head a bit, explains some of the issues and invites some suggestions and tricks from readers.

Fun Conversions

The Basics of Good T-SQL Coding Style – Part 4: Performance

There are several obvious problems with poor SQL Coding habits. It can make code difficult to maintain, or can confuse your team colleagues. It can make refactoring a chore or make testing difficult. The most serious problem is poor performance. You can write SQL that looks beautiful but performs sluggishly, or interferes with other threads. A busy database developer adopts good habits so as to avoid staring at execution plans. Rob Sheldon gives some examples.