For an instructor lead, in-depth look at learning SQL click below.
In this post, I’ll take you on a journey to build a simple blogging platform using Structure Query Language (SQL), the standard language for dealing with relational databases.
Step 1: Design the Database
The first step is designing our database. We’ll need three main tables: Users, Blogs, and Comments.
Creating the Users Table:
|
1 2 3 4 5 6 7 8 |
CREATE TABLE Users ( UserID INT PRIMARY KEY, Username VARCHAR(50) NOT NULL, Email VARCHAR(50) NOT NULL UNIQUE, Password VARCHAR(50) NOT NULL ); |
This table will store our users’ information. Each user will have a unique UserID, a Username, an Email, and a Password.
Creating the Blogs Table:
|
1 2 3 4 5 6 7 8 9 |
CREATE TABLE Blogs ( BlogID INT PRIMARY KEY, UserID INT FOREIGN KEY REFERENCES Users(UserID), Title VARCHAR(100) NOT NULL, Content TEXT NOT NULL, DatePosted DATE NOT NULL ); |
This table will store the blogs. Each blog post will have a unique BlogID, the UserID of the author (reference to the Users table), a Title, Content, and the Date when it was posted.
Creating the Comments Table:
|
1 2 3 4 5 6 7 8 9 |
CREATE TABLE Comments ( CommentID INT PRIMARY KEY, UserID INT FOREIGN KEY REFERENCES Users(UserID), BlogID INT FOREIGN KEY REFERENCES Blogs(BlogID), Content TEXT NOT NULL, DatePosted DATE NOT NULL ); |
Lastly, the Comments table will store the comments for each blog post. Each comment will have a unique CommentID, the UserID of the commenter, the BlogID of the blog post it’s for (both are references to the other tables), the Comment content, and the Date when it was posted.
Step 2: Querying the data
Once the data is inserted into these tables, it can be used to display it on the blog. For example, if you want to show all of the blog posts written by a certain user:
|
1 2 3 4 5 |
SELECT Blogs.Title, Blogs.Content, Blogs.DatePosted FROM Blogs INNER JOIN Users ON Blogs.UserID = Users.UserID WHERE Users.Username = 'username'; |
Conclusion
Building a blog using SQL is a straightforward process once you understand relational data modeling, primary and foreign keys, and of course, SQL syntax. As ever in coding, practice makes perfect – so give it a try!