Day 10. Views and Temporary Tables

Up to this point in your reading, you have learned quite a lot about the SELECT statement and how you can use it to retrieve and manipulate data from a database. You have also learned how to use the INSERT, UPDATE, and DELETE statements to further manipulate the data in the database. In fact, you used a SELECT statement to retrieve data from one table and insert it into another table. Along the way, you also learned about joins, indexes, and the functions that you can use in a SQL query. In today's lesson, you will learn about two unique and very different features of SQL that you can use: temporary tables and views.

Temporary tables are very much like regular tables, except that you create them as needed and they are cleanly deleted at the end of the process. A view is just what its name implies: a way of looking at or viewing columns from one or more tables as a single entity.

The topics that we will cover today include

• What is a view?

• Working with views

• Using the SQL UNION keyword

• What is a temporary table?

• Creating a temporary table

• Real versus temporary tables

• Local and global temporary tables