 In this learning activity, we will discover what CRUD, or CRUD, applications are, and how they're used in everyday life. Let's get right to it. CRUD stands for the four types of operations you typically do with a database. Create, Retrieve, Update, and Delete. It might seem strange to devote an entire learning activity to these applications. It might even seem boring, but applications that use these operations, or CRUD apps as they're called, make up a vast majority of the computer programs in use today. Create for whenever we add a new record to a database. Retrieve for whenever we search for an existing record. Update for whenever we change something in an existing record. Delete for whenever we delete an existing record. Let's look at some typical CRUD apps we use all the time. Let's consider the very popular website, Blamazon.com. That's right, Blamazon.com is a huge CRUD app. Let's say you've never been to Blamazon, you've never used it. What's the first thing you do? Well, create an account, of course. Does that mean a new record gets created in the Blamazon database somewhere? You bet it does. More specifically, there's a data table somewhere in the Blamazon database. Let's say it's named Customers. A data table is a huge list that exists in a database. You might have a table for Customers, a table for Orders, a table for Addresses. You might also have tables that you only read, such as zip codes or countries. Place design is an art all unto itself. Let's not go down that rabbit hole now. For now, Blamazon has a table named Customers. That's simply a list of the site's customers. Okay, so what makes up a customer? All the data that Blamazon feels it needs to store about each customer. That might include their name, password data, warning, can of worms, email address, date of birth, that kind of thing. Create. Let's say you filled out the new Blamazon user form online and have just hit the Save button. The data is packaged up and sent from the web browser to the web server, which turns around and saves it in the database. Since your record doesn't yet exist, it needs to create a new record. In a data table, this record is called a row. Just like a ledger or spreadsheet, think of a table as having columns, name, email, etc. And each row is a different record. The SQL statement required to create a new record might look like this. Retrieve. Now that Blamazon knows who you are, you can log in. Logging into Blamazon gives you a personal experience. You can easily access your video library, your past orders, etc. Blamazon might even suggest a new book or video for you. So you go to the login page, enter your email address and password, and the web server retrieves your record from the database. Once it has your data, it can create that custom view just for you. In SQL, the command to retrieve the data is Select. Use a typical Select command. Update. By now I think you can see the pattern. You realize that when you signed up, you told Blamazon you were born in the year 1910. So you log into Blamazon and edit your profile. You change your birth date and hit the Save button. This time, instead of performing an Insert command, the website is going to perform an Update command to change your birth date. The SQL might look like this. This statement tells the database to update the row in the table named Customers, in which the email column is set to Carl at franklins.net, and change or update the date of birth column to 4.19.19.90. Delete. As it turns out, you didn't like the experience of changing your birth date, so you decide to do a Rage Quit of Blamazon. You're taking your marbles and going home. You tell Blamazon to delete your account. You no longer want to use Blamazon. You're done. After a bit of digital begging and cajoling, Blamazon lets you hit the Big Delete Me button, and on the back end, the command might look like this. Poof, you're gone. The corporate world is full of crud apps, or applications that do these four basic operations on a database. Create for adding records, retrieve for retrieving or selecting records, update for updating or editing records, and delete for deleting records. In this learning activity, we learned the meaning of crud. We walked through a real-world example of an application that uses crud operations, and we got a taste of the SQL language for interacting with databases.