Learn what aggregate functions are, how to use them in SQL queries, and why they are useful for BI. Find examples of common scenarios and calculations.

SQLite has nice feature which allows to register custom aggregate functions written in C (and Lua in case of Tarantool) and available from SQL like any other. Example is count_x() which counts numb ...

If you have an aggregation function (sum, avg, count) in your select clause or if you have a group by clause, all of your columns must be aggregated or grouped.<BR><BR>In the version of SQL that I ...

Sometimes you need to perform some complex SQL queries depending on some aggregate operations or functions. In most cases, these complex operations could be achieved by series of queries with joins ...

Anyone know the best way to write a median aggregate function in ms sql server 2k? I've seen a couple ways of doing it when I briefly searched google but they weren't presented as functions.