MySQL

Choosing Column Types

The previous section describes the various MySQL column types from which you can choose and the general properties of those types, such as the kind of values they may contain, how much storage space they take, and so on. But how do you actually decide which types to use when you create a table? This section discusses issues to consider that will help you choose.

The most "generic" column types are the string types. You can store anything in them because numbers and dates can be represented in string form. So why not just declare all your columns as strings and be done with it? Let's consider a simple example. Suppose you have values that look like numbers. You can represent these as strings, but should you? What happens ...