argument = $argument; } function getExpression($with_value = true){ return "$this->column_name = $this->argument"; } function getValue(){ // TODO Escape value according to column type instead of variable type $value = $this->argument; if(!is_numeric($value)) return "'".$value."'"; return $value; } function show(){ if(!$this->argument) return false; $value = $this->argument; if(!isset($value)) return false; return true; } function getArgument(){ return null; } function getArguments(){ return array(); } } ?>