Programming for SQL Products – The Basics
MySQL programming, like all programming and software development, relies on a small set of core ideas. Variables are an important part of that idea set, and we'll see how they work as we begin to work with MySQL.
When we build programs in MySQL or in any other software development language, we use variables as buckets to hold information, or values, that the programs need. A variable has a name, and in most software products—including MySQL—it has an information type. In a structured, predictable way, the program can change the value of a variable based on the behavior of the program, information that comes into the program from outside of the program, or both. A variable will reliably hold the last value assigned to it. Before we look at SQL stored procedures and functions, we'll see how variables operate in MySQL.
Launch MySQL and place the following statements in the editor or the query window:
SET...