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## Chapter 9 Language Structure 

## Table of Contents 

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This chapter discusses the rules for writing the following elements of SQL statements when using MySQL: 

## 9.1 Literal Values 

•Literal values such as strings and numbers 

•Identifiers such as database, table, and column names 

•Keywords and reserved words 

•User-defined and system variables 

•Expressions 

•Query attributes 

•Comments 

This section describes how to write literal values in MySQL. These include strings, numbers, hexadecimal and bit values, boolean values, and NULL . The section also covers various nuances that you may encounter when dealing with these basic types in MySQL. 

## 9.1.1 String Literals 

A string is a sequence of bytes or characters, enclosed within either single quote ( ’ ) or double quote ( " ) characters. Examples: 

’a string’ "another string" 

