SQL Queries for Mere Mortals: A Hands-On Guide to Data Manipulation in SQL, 4th Edition

17Deleting Sets of Data

“I came to love my rows, my beans, though so many more than I wanted.”

—HENRY DAVID THOREAU

Topics Covered in This Chapter

What Is a DELETE?

The DELETE Statement

Uses for DELETE

Sample Statements

Summary

Problems for You to Solve

Now you know how to change data by using an UPDATE statement. You also have learned how to add data by using an INSERT statement. But what about getting rid of unwanted data? For that, you need to use what is arguably the simplest but also the most dangerous statement in SQL—DELETE.

What Is a DELETE?

You learned in the previous chapter that adding data to your tables is fairly straightforward. You can add one row at a time by using a VALUES clause, or you can copy multiple rows by using a SELECT ...