CRUD Operations are typically performed on databases, hence, in this PHP CRUD Operations tutorial, you will implement CRUD techniques on MySQL databases with the help of PHP.
The CRUD acronym comprises all the major operations that are performed on a relational database. It stands for:
C = Create
R = Read
U = Update
D = Delete
You will now understand the different operations in detail.
How to Create a MySQL Database Connection?
First, create a connection between the database and your PHP code.
The following code acts as the connection between the webpage and the database where the data from the webpage will be stored.
Here, name the file as config.php
<?php $servername = "localhost";$username = "root"; $password = ""; $dbname = "mydb"; $conn = new mysqli($servername, $username, $password, $dbname);if ($conn->connect_error) { die("Connection failed: " . $conn->connect_error);}?>
How to Create Records?
The first operation in PHP CRUD Operations, Create, is responsible
for creating tables or new records into an existing table. To do that,
first, you must write the code for the webpage to create an entry in the
database.
Name the file as create.php.
<?php include "config.php"; if (isset($_POST['submit'])) { $first_name = $_POST['firstname']; $last_name = $_POST['lastname']; $email = $_POST['email']; $password = $_POST['password']; $gender = $_POST['gender']; $sql = "INSERT INTO `users`(`firstname`, `lastname`, `email`, `password`, `gender`) VALUES ('$first_name','$last_name','$email','$password','$gender')"; $result = $conn->query($sql); if ($result == TRUE) { echo "New record created successfully."; }else{ echo "Error:". $sql . "<br>". $conn->error; } $conn->close(); }?>nbsp;html><h2 id="Signup-Form">Signup Form</h2>
This page displays a signup form that stores the details entered on the page into the table named ‘users’.
How to Read/View Records?
The second operation, just as the name suggests, ‘Read’ is used to display or read the data that is already available in the database.
To perform the operation, you need to create a page that displays the records from the table ‘users’.
Now, name the page as view.php
<?php include "config.php";$sql = "SELECT * FROM users";$result = $conn->query($sql);?>nbsp;html> <title>View Page</title><link> <div> <h2 id="users">users</h2> <table> <thead> <tr> <th>ID</th> <th>First Name</th> <th>Last Name</th> <th>Email</th> <th>Gender</th> <th>Action</th> </tr> </thead> <tbody> <?php if ($result->num_rows > 0) { while ($row = $result->fetch_assoc()) { ?> <tr> <td><?php echo $row['id']; ?></td> <td><?php echo $row['firstname']; ?></td> <td><?php echo $row['lastname']; ?></td> <td><?php echo $row['email']; ?></td> <td><?php echo $row['gender']; ?></td> <td> <a>Edit</a> <a>Delete</a> </td> </tr> <?php } } ?> </tbody> </table> </div>
How to Update Records?
The third operation i.e, ‘update’ is used to change or modify the already existing data present in the database.
To do this, you need to create another page to update the details in the database. Here, name the page as update.php
<?php include "config.php"; if (isset($_POST['update'])) { $firstname = $_POST['firstname']; $user_id = $_POST['user_id']; $lastname = $_POST['lastname']; $email = $_POST['email']; $password = $_POST['password']; $gender = $_POST['gender']; $sql = "UPDATE `users` SET `firstname`='$firstname',`lastname`='$lastname',`email`='$email',`password`='$password',`gender`='$gender' WHERE `id`='$user_id'"; $result = $conn->query($sql); if ($result == TRUE) { echo "Record updated successfully."; }else{ echo "Error:" . $sql . "<br>" . $conn->error; } } if (isset($_GET['id'])) { $user_id = $_GET['id']; $sql = "SELECT * FROM `users` WHERE `id`='$user_id'"; $result = $conn->query($sql); if ($result->num_rows > 0) { while ($row = $result->fetch_assoc()) { $first_name = $row['firstname']; $lastname = $row['lastname']; $email = $row['email']; $password = $row['password']; $gender = $row['gender']; $id = $row['id']; } ?> <h2 id="User-Update-Form">User Update Form</h2>
The above is the detailed content of The Best Guide to PHP CRUD Operations You'll Ever Need. For more information, please follow other related articles on the PHP Chinese website!

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