MariaDB Crash Course

22. Using Views

In this chapter you learn exactly what views are, how they work, and when they should be used. You also see how views can be used to simplify some of the SQL operations performed in earlier chapters.

Understanding Views

Views are virtual tables. Unlike tables that contain data, views simply contain queries that dynamically retrieve data when used.

The best way to understand views is to look at an example. Back in Chapter 15, “Joining Tables,” you used the following SELECT statement to retrieve data from three tables:

Input

SELECT cust_name, cust_contact FROM customers, orders, orderitems WHERE customers.cust_id = orders.cust_id   AND orderitems.order_num = orders.order_num   AND prod_id = 'TNT2';

That query was used to retrieve ...