If you have ever been to a sandwich shop, you have seen a long counter with containers of various lengths and sizes. Each of these containers has a specific purpose— some hold meat, others hold cheese, and others hold vegetables; there are even containers for the sauces. However, as a customer you may not need or want each item from every container to be on your sandwich, but everyone once in a while it can be fun to order–everything.

All of a sudden I am feeling very hungry.

Your database is set up in a similar fashion. There are different buckets for different components of the system. We call these components objects and our challenge as a data professional is to use the appropriate objects, or ingredients if you are hungry, to satisfy the needs of our client—an end user or an application.   This site focuses on all you will need to know to create and edit objects while getting data in and out too.

To get started with the components of your database, check out these links.



Primary Keys




Want to follow along on your own database?

Do you want to follow along with the examples?  We have created a sample database you can use to follow along and try in your own database.  Go to the download page and follow the instructions.  Have fun on the SQL trail!