PHP MySQL Delete Data

🗑️ PHP MySQL Delete Data Tutorial

The DELETE statement is used to remove records from a MySQL table. In PHP, you can execute DELETE queries using mysqli or PDO.

⚠️ Warning: Without a WHERE clause, DELETE will remove all rows in the table.

1️⃣ Using `mysqli` (Procedural)

<?php
$conn = mysqli_connect("localhost", "root", "", "test_db");

if (!$conn) {
die("Connection failed: " . mysqli_connect_error());
}

// Delete specific record
$sql = "DELETE FROM users WHERE id=3";

if (mysqli_query($conn, $sql)) {
echo "Record deleted successfully";
} else {
echo "Error deleting record: " . mysqli_error($conn);
}

mysqli_close($conn);
?>

<?php

$conn = mysqli_connect("localhost", "root", "", "test_db");

if (!$conn) {

die("Connection failed: " . mysqli_connect_error());

}

// Delete specific record

$sql = "DELETE FROM users WHERE id=3";

if (mysqli_query($conn, $sql)) {

echo "Record deleted successfully";

} else {

echo "Error deleting record: " . mysqli_error($conn);

}

mysqli_close($conn);

✅ Deletes the record where id = 3.

2️⃣ Using `mysqli` Object-Oriented

<?php
$conn = new mysqli("localhost", "root", "", "test_db");

if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}

// Delete record
$sql = "DELETE FROM users WHERE name='Ravi'";

if ($conn->query($sql) === TRUE) {
echo "Record deleted successfully";
} else {
echo "Error deleting record: " . $conn->error;
}

$conn->close();
?>

<?php

$conn = new mysqli("localhost", "root", "", "test_db");

if ($conn->connect_error) {

die("Connection failed: " . $conn->connect_error);

}

// Delete record

$sql = "DELETE FROM users WHERE name='Ravi'";

if ($conn->query($sql) === TRUE) {

echo "Record deleted successfully";

} else {

echo "Error deleting record: " . $conn->error;

}

$conn->close();

✅ Object-oriented style uses $conn->query().

3️⃣ Using PDO

<?php
try {
$conn = new PDO("mysql:host=localhost;dbname=test_db", "root", "");
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

// Delete record using prepared statement
$stmt = $conn->prepare("DELETE FROM users WHERE age < :age");
$age = 28;
$stmt->bindParam(':age', $age);
$stmt->execute();

echo "Record(s) deleted successfully";

} catch(PDOException $e) {
echo "Error: " . $e->getMessage();
}

$conn = null; // Close connection
?>

<?php

try {

$conn = new PDO("mysql:host=localhost;dbname=test_db", "root", "");

$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

// Delete record using prepared statement

$stmt = $conn->prepare("DELETE FROM users WHERE age < :age");

$age = 28;

$stmt->bindParam(':age', $age);

$stmt->execute();

echo "Record(s) deleted successfully";

} catch(PDOException $e) {

echo "Error: " . $e->getMessage();

}

$conn = null; // Close connection

✅ Using prepared statements ensures security against SQL injection.

4️⃣ Delete All Records

⚠️ Always be careful! Use WHERE to avoid removing all records unintentionally.

5️⃣ Key Points

DELETE removes one or more records from a table.
Always include a WHERE clause unless you intend to delete all records.
Use prepared statements for dynamic or user-supplied data.
mysqli_query() or $conn->query() executes the DELETE query.
For PDO, use prepare() and execute() for safety.

PHP MySQL Delete Data