Added related model updating from belongs_to relationship.

laravel/database/eloquent/model.php

@@ -174,6 +174,22 @@ abstract class Model {
 		return ($success) ? $model : false;
 	}
 
+	/**
+	 * Update a model instance in the database.
+	 *
+	 * @param  mixed  $id
+	 * @param  array  $attributes
+	 * @return int
+	 */
+	public static function update($id, $attributes)
+	{
+		$model = new static(array(), true);
+
+		if (static::$timestamps) $attributes['updated_at'] = $model->get_timestamp();
+
+		return $model->query()->where($model->key(), '=', $id)->update($attributes);
+	}
+
 	/**
 	 * Find a model by its primary key.
 	 *