Getting to Know the Project

Hi I'm Alena, a PHP teacher at Treehouse. 0:01 I'm going to be teaching you how to connect a basic PHP website to a database. 0:08 This will allow you to dynamically update your web pages 0:12 with constantly changing information. 0:15 You already know the basics of PHP but 0:18 building a PHP driven page is just the first step in mastering PHP. 0:21 The true power of PHP shines when you connect it to a data source, 0:27 like an API or a database. 0:31 To introduce you to databases, we'll start with an example project, 0:33 a personal media library. 0:37 Currently the application is pretty simple and 0:39 it stores its data in an associative array. 0:42 An associative array can become extremely hard to maintain. 0:45 Since it's just text, we could easily miss adding a piece of information. 0:49 We could also mistype the name of a field, 0:54 which would stop our site from using it at all. 0:56 We could handle these issues, by writing our own interface with PHP. 1:00 However, one of the first things you should learn about programming is, 1:05 don't reinvent the wheel. 1:09 Use the right tool for the job, a database is designed to store data. 1:11 If you need to store data, like our media items, a database is a good choice. 1:16 Another important thing to consider, 1:22 anytime we want to use the data that stored in an array. 1:24 We need to include the entire array, even if we only need one item. 1:28 With twelve items, this is not really an issue. 1:33 But with 1,200 items, things can really start to slow down. 1:35 A database can also give us more advanced sorting and search capabilities. 1:40 We'll refactor that application to use a database to store the media items. 1:46 This will make our application easier and faster to scale. 1:51 It also makes it easier and faster to add functionality. 1:54 We'll be adding search and pagination functionality to this project. 1:58 Using this library data, 2:02 we'll learn how to communicate using php's data objects or pto for short. 2:04 Pto uses object oriented methodology, 2:10 which makes interacting with databases very efficient. 2:13 We'll be covering everything you need to know, so 2:16 don't be afraid if you don't understand object oriented programming. 2:18 We'll be using relational databases for 2:23 this project because it fits well with the way our data relates to each other. 2:25 To learn more about relational databases, 2:30 make sure you check the teacher's notes for more great courses. 2:32 For now, let's take a look at the way our data is structured. 2:36 The table structure that we'll be working with has a media table, a genre table and 2:40 a people table. 2:44 There is only one genre assigned to each item, so 2:45 we can link directly from the media table to the genre's table. 2:48 On the other hand, there are multiple people assigned to each item. 2:52 So, we link the media and the people table together, using another table. 2:56 That table also tells us which role that person performs. 3:01 For example, the movie Office Space has a director, Mike Judge and 3:05 stars Ron Livingston, Jennifer Aniston, and David Herman. 3:10 This simple structure will allow you to practice with relational data, 3:16 as you learn your way around a database. 3:20 For reference, I've also included a chart in the teacher's notes 3:22 that describes the database structure. 3:26 Our main focus will be in the media table and 3:28 we'll be pulling supporting information from the other tables. 3:31 Let's take a look at our project. 3:34 If you open the workspace attached to this video, you'll see all the files for 3:37 our personal media library. 3:40 You'll also see a database file within the includes folder, named database.db. 3:41 Our database file is local to the workspace, so 3:48 it's really great for you to be able to play with. 3:51 Don't be afraid to experiment and try out different things with the database. 3:54 You can always replace the file with a fresh copy. 3:57 In workspaces we'll be using SQlite. 4:01 However, most of the query commands will be the same, 4:04 no matter which relational database you use. 4:07 Where SQlite differs, I'll highlight those differences and 4:10 add them to the teacher's notes. 4:12 You're also welcome to download the project files and install them locally. 4:14 Within the download, I've also included a dot sequel file for 4:18 importing the data into another database, such as my sequel. 4:21 Check the teachers notes, if you need more instruction. 4:25 When we go over and 4:28 hit preview, we can see how the application works in the browser. 4:29 On the home page, 4:33 we are showing four random media items, each time the page is loaded. 4:34 We also have the links at the top to view the library categories, books, 4:38 movies and music. 4:44 From the category pages we can also link to the full catalog, 4:46 there is also a link to this suggest page. 4:50 Which includes a form for sending a suggestion for a new media item. 4:52 After connecting to the database, we'll add a couple new features. 4:56 So, let's take a look at the finished site as well. 5:00 First of all we'll be adding a search feature. 5:02 Can you imagine browsing the internet without the ability to search? 5:05 The internet is full of information on almost anything you can think of. 5:09 But how would we possibly find it, without the ability to search? 5:12 In this course we'll be introducing you to some of the basic components of search. 5:17 By adding the ability to search the media library. 5:21 Another useful item as our catalog grows is pagination. 5:24 Listing a million items on a single page would make for a really slow loading page. 5:28 Can you imagine trying to shop on Amazon if every single item was on one page? 5:33 Pagination allows us to split the items across multiple pages and 5:38 navigate between those pages. 5:42 It's kind of like the old adage, how do you eat an elephant, one bite at a time. 5:44 Pagination allows us to give our users the data in bite sized chunks. 5:50 Finally, we'll use our database to simplify our form drop downs as well. 5:55 All this code- Will be simplified into this function. 6:00 Currently all the data about the items used in our application 6:07 is stored in an array. 6:11 Moving the data to a database will give us more flexibility for organization. 6:13 And allows us to select only part of the data 6:18 without having to loop through each item in the array. 6:21 This becomes even more important as our data set grows. 6:24 Our first step is to look at the php data object 6:28 to set up the connection to the database. 6:31 So let's get started 6:33