Beginner's SQL: Aggregates and Grouping Support

When you create a database-driven Web site, you will encounter a number of common data retrieval scenarios. Simple lists, header/detail listings, row difference calculations, and reports with subtotals can all be satisfied using fairly basic SELECT queries. But when you move on to functions that aggregate data - to find sums, averages, counts and the like, there's a few gotchas that can baffle the newbie and trip up even the experienced developer.

Wave goodbye to Aggregate and groupings gotcha misery with Rudy's easy-to-follow tutorial on some of SQL's powerful aggregating functions!