How to delete records from database using PHP

Deleting data in the database is a very common operation. In this article, we will explain how to delete records from a database using PHP. If you are a PHP developer or are learning PHP development, this article is a must!

1. Connect to the database

First, you need to connect to the MySQL server. For this you can use a PHP function mysqli_connect(). This function requires 4 parameters: hostname, username, password and database name. For example:

$host = "localhost";
$user = "username";
$password = "password";
$db_name = "database_name";

$conn = mysqli_connect($host, $user, $password, $db_name);

2. Check whether the connection is valid

After connecting to the database, you need to check whether the connection is successful. You can use a mysqli_affected_rows() function in PHP. If the return value is positive, the connection is successful. Otherwise, it returns a negative number. The following is a practical example:

if(mysqli_affected_rows($conn) === -1) {
    die("Error: Connection failed!");
}

3. Prepare SQL statement

Now you need to prepare a SQL statement to delete a record in the database. First, you need to select the tables and records you want to delete. For example, if you have a table called "users", you can use the following code:

$table_name = "users";
$id = $_GET['id'];

$sql = "DELETE FROM $table_name WHERE id = $id";

In the above code, we are using the $id variable, which is obtained from the $_GET array, which Contains all parameters sent to the server via the GET method.

Please note that we are using double quotes ("") to surround the variable and adding a $ sign in front of the variable. This will let the PHP interpreter know that this is a variable name and not a string constant.

4. Execute the SQL statement

Next, you need to send the SQL statement to the database and execute it. There is a mysqli_query() function that can help you achieve this. Here is the code sample:

$result = mysqli_query($conn, $sql);

if(!$result) {
    die("Error: Could not delete record!");
}

5. Close the database connection

Finally, after completing the connection and operation with the database, it is best to close the connection. This can be achieved through the mysqli_close() function:

mysqli_close($conn);

Full code example:

$host = "localhost";
$user = "username";
$password = "password";
$db_name = "database_name";

$conn = mysqli_connect($host, $user, $password, $db_name);

if(mysqli_affected_rows($conn) === -1) {
    die("Error: Connection failed!");
}

$table_name = "users";
$id = $_GET['id'];

$sql = "DELETE FROM $table_name WHERE id = $id";

$result = mysqli_query($conn, $sql);

if(!$result) {
    die("Error: Could not delete record!");
}

mysqli_close($conn);

This is how to delete a record from the database using PHP. We hope this article helps you better understand how to handle data and make your PHP development more efficient and optimized.

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