How to implement data deletion function using MySQL and PHP development
How to implement the data deletion function using MySQL and PHP development
Title: How to implement the data deletion function using MySQL and PHP development
In the development process of many websites and applications, we often The data in the database needs to be deleted. This function can be easily achieved using a combination of MySQL and PHP. This article will introduce how to use MySQL and PHP development to implement the data deletion function, and provide corresponding code examples.
1. Establish database and tables
First, we need to create a database and corresponding tables to store the data to be operated. Suppose we want to delete user information, we can create a table named "users" that contains the following fields: ID (independent user ID), name (user's name), age (user's age), and email (user's email address). Mail).
CREATE DATABASE mydatabase;
USE mydatabase;
CREATE TABLE users (
id INT(6) UNSIGNED AUTO_INCREMENT PRIMARY KEY, name VARCHAR(30) NOT NULL, age INT(3) NOT NULL, email VARCHAR(50), reg_date TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
);
2. Connect to the database
Next , we need to connect to the MySQL database in PHP code.
$servername = "localhost";
$username = "root";
$password = "password";
$dbname = "mydatabase";
$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
echo "Connected successfully";
?>
3. Delete data
After establishing the database connection, we can write code to implement the function of deleting data. Below is a sample code to delete user data with a specific ID.
$userid = 1; //Specify the user ID to be deleted
$sql = "DELETE FROM users WHERE id=$userid";
if ($conn->query($sql) === TRUE) {
echo "Record deleted successfully";
} else {
echo "Error deleting record: " . $conn->error;
}
?>
In the above code, we delete the user data of the specified ID by executing the SQL statement "DELETE FROM users WHERE id=$userid". If the deletion is successful, "Record deleted successfully" will be output, otherwise an error message will be output.
4. Complete sample code
The following is a complete sample code that shows how to use MySQL and PHP to implement the data deletion function.
connect_error) { die("Connection failed: " . $conn->connect_error); } echo "Connected successfully"; $userid = 1; // 指定要删除的用户ID $sql = "DELETE FROM users WHERE id=$userid"; if ($conn->query($sql) === TRUE) { echo "Record deleted successfully"; } else { echo "Error deleting record: " . $conn->error; } $conn->close(); ?>
The above code can be executed on a server with appropriate MySQL and PHP environments to achieve the deletion of user data.
Summary:
Using the combination of MySQL and PHP, we can easily implement the data deletion function. By connecting to the MySQL database and writing appropriate SQL statements, we can delete specific data in the database. This article provides code examples for establishing databases and tables, connecting to databases, and deleting data for readers' reference and practice. This feature is very common in many applications and it can be of great help to us whether we are deleting users, deleting comments or deleting other types of data.
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