Sams Teach Yourself SQL in 10 Minutes, Fourth Edition

Lesson 6. Using Wildcard Filtering

In this lesson, you’ll learn what wildcards are, how they are used, and how to perform wildcard searches using the LIKE operator for sophisticated filtering of retrieved data.

Using the LIKE Operator

All the previous operators we studied filter against known values. Be it matching one or more values, testing for greater-than or less-than known values, or checking a range of values, the common denominator is that the values used in the filtering are known.

But filtering data that way does not always work. For example, how could you search for all products that contained the text bean bag within the product name? That cannot be done with simple comparison operators; that’s a job for wildcard searching. Using wildcards, ...