sql语句查询30内天到期数据，sql根据时间戳查询30天内到期的数据

SELECT
service_item.start_date,
service_item.end_date,
unix_timestamp(now()) as Today,
service_item.end_date-unix_timestamp(now()) as Subtracting,
round((service_item.end_date-unix_timestamp(now()))/86400) as due,


FROM
service_item

WHERE round((service_item.end_date-unix_timestamp(now()))/86400)>=0

获取当期（今天）的时间戳

unix_timestamp(now()) as Today,

到期时间戳减去当期时间戳
service_item.end_date-unix_timestamp(now()) as Subtracting,

期时间戳减去当期时间戳，除以86400（一天的时间的毫秒数），然后用sql round()函数四舍五入取整，得到到期天数
round((service_item.end_date-unix_timestamp(now()))/86400) as due,