/**
* Adjust the value of a column up or down by a given amount.
*
* @param string $column
* @param int $amount
* @param string $operator
* @return int
*/
protected function adjust($column, $amount, $operator)
{
// To make the adjustment to the column, we'll wrap the expression
// in an Expression instance, which forces the adjustment to be
// injected into the query as a string instead of bound.
$value = Database::raw($this->grammar->wrap($column) . $operator . $amount);
return $this->update(array($column => $value));
}
