mysql 统计今日、本周、本月sql语句

//时间为时间戳
$day = "TO_DAYS(FROM_UNIXTIME(clock)) = TO_DAYS(NOW())"; //今日
$week = "WEEKOFYEAR(FROM_UNIXTIME(clock))=WEEKOFYEAR(NOW())";  //本周
$month = "FROM_UNIXTIME(clock, '%Y-%m') = DATE_FORMAT(CURDATE(),'%Y-%m')"; //本月