Data Analytics & Visualization All-in-One For Dummies

Chapter 2

Drilling Down to the SQL Nitty-Gritty

IN THIS CHAPTER

Executing SQL statements

Using (and misusing) reserved words

Working with SQL’s data types

Handling null values

Applying constraints

This chapter gets into the nitty-gritty of SQL. This is knowledge you need to master before you embark on actually writing SQL statements. SQL has some similarities to computer languages you may already be familiar with and some important differences. The chapter touches on some of these similarities and differences, but others are discussed later in this book (Book 4) at the appropriate points in a complete discussion of SQL.

Executing SQL Statements

SQL is not a complete language, but a data sublanguage. As such, you cannot write a program in the SQL language like you can with C or Java. That doesn’t mean SQL is useless, though. There are several ways that you can use SQL. Say you have a query editor up on your screen, and all you want is the answer to a simple question. Just type an ...