Basic Structured Query Language (SQL)
Jonathan Eckstein, Bonnie R. Schultz · 2017
This chapter presents the basics of Structured Query Language (SQL) through numerous examples. It describes all the principle components of the SELECT statement, including the FROM, WHERE, and ORDER BY clauses. It covers aggregation queries, including aggregation functions, the GROUP BY clause, the HAVING clause, and how WHERE and HAVING differ. It also describes the principles of inner joins and the conceptual sequence of operations in every SELECT query.