Summary

This chapter covered the basics that are required to understand SQL. We briefly discussed how SQL works and its evolution as a global standard for database access.

The chapter then moved on to look at exactly what's meant by the term database, as well as several concepts that together relate to the way data is stored. You saw that databases consist of tables that contain rows of data, where each row contains a single data entry that's made up of entries in several columns. You also saw that a row in a table must have a unique primary key value in order to differentiate it from other rows in the same table.

You then learned how you can relate tables together in a relational database and the types of relationships that can exist between tables.

Finally, you had your first look at the basics of SQL, including comment syntax.

For the rest of this book, you'll look at how to use the SQL introduced in this chapter, and you'll use the terms defined in this chapter continuously. Trust us— give it a few more chapters, and these terms will be indelibly etched in your mind (if they aren't already), so there's no danger of forgetting any of them!