on delete cascade eloquent code example

Example 1: laravel delete relationship data

class User extends Eloquent
{
    public function photos()
    {
        return $this->has_many('Photo');
    }

    // this is a recommended way to declare event handlers
    public static function boot() {
        parent::boot();

        static::deleting(function($user) { // before delete() method call this
             $user->photos()->delete();
             // do the rest of the cleanup...
        });
    }
}

Example 2: on delete cascade

CREATE TABLE child_table
(
  column1 datatype [ NULL | NOT NULL ],
  column2 datatype [ NULL | NOT NULL ],
  ...

  CONSTRAINT fk_name
    FOREIGN KEY (child_col1, child_col2, ... child_col_n)
    REFERENCES parent_table (parent_col1, parent_col2, ... parent_col_n)
    ON DELETE CASCADE
    [ ON UPDATE { NO ACTION | CASCADE | SET NULL | SET DEFAULT } ] 
);