Common Europe Congress 2023

An SQL SELECT can be much more than a simple SELECT * FROM query. Among others it includes with the GROUP BY clause a powerful data aggregation capability. A bunch of aggregate functions allows to count or summarize rows, to calculate the average over multiple rows, to determine the minimum and maximum row value. The GROUP BY clause may be widely known and used, but the HAVING clause which goes hand in hand with the GROUP BY is often a mystery. There may be other secrets waiting for being revealed … or did you know you can create all kinds of sub-totals and grand-total with an SQL GROUP BY?

Learning Objectives:
In this session you’ll learn the basic use of the GROUP BY and HAVING clauses as well as the use of multiple aggregate functions. You’ll also discover how NULL values can affect the result returned by aggregate functions. It will be demonstrated how easily all kinds of sub-totals and grand-totals can be built. You’ll also learn how to use the CASE clause for building pivot tables.