Deleting data is a common operation in CRUD (Create, Read, Update, Delete).

In CodeIgniter, we can delete records using:

1. Query Builder (Active Record) – recommended way
2. Raw SQL Queries – when you need more control

🔹 Step 1: Load Database

Make sure the database is connected:

$autoload['libraries'] = array('database');

Or load manually in the controller:

$this->load->database();

🔹 Step 2: Delete a Record by ID

class DeleteController extends CI_Controller {

    public function delete_user($id) {
        $this->db->where('id', $id);
        $this->db->delete('users');  // DELETE FROM users WHERE id=?

        if ($this->db->affected_rows() > 0) {
            echo "User deleted successfully!";
        } else {
            echo "No record found!";
        }
    }
}

👉 Example URL:

http://your-site/index.php/deletecontroller/delete_user/1

🔹 Step 3: Delete with Multiple Conditions

public function delete_inactive_users() {
    $this->db->where('status', 0);
    $this->db->where('email LIKE', '%@example.com');
    $this->db->delete('users');  // DELETE FROM users WHERE status=0 AND email LIKE '%@example.com'

    echo $this->db->affected_rows() . " inactive users deleted!";
}

🔹 Step 4: Delete All Records (Be Careful ⚠️)

public function delete_all_users() {
    $this->db->empty_table('users'); // TRUNCATE TABLE users
    echo "All users deleted!";
}

🔹 Step 5: Delete Using Raw SQL

public function delete_with_limit() {
    $sql = "DELETE FROM users WHERE status = 0 LIMIT 5";
    $this->db->query($sql);
    echo "5 inactive users deleted!";
}

🔹 Step 6: Delete Using Form Input

public function delete_from_form() {
    $id = $this->input->post('id');

    $this->db->where('id', $id);
    $this->db->delete('users');

    echo "User with ID $id deleted!";
}

🔹 Example Output

Before delete:

ID: 3 | Name: Alex | Email: alex@example.com | Status: 0

After delete:

Record with ID 3 removed from database.