Data3 HK 2017

Abstract: 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-totals with SQL?
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.
Audience: Programmers, Database Administrators and Engineers who quite often need to run queries
or built reports that include sub-totals and grand totals. Everybody who is interested in what
can be done with an SQL SELECT statement.