为什么是取得1,2,3,5,7,9,14天内的累计数据？而不是第1,2,3,5,7,9,14天的单独一天的数据
代码片段大概是这个样子：
SELECT a.* FROM(
SELECT a.,DATEDIFF('2015/12/14',DATE)AS days FROM(
SELECT a.,FLOOR((DATEDIFF('2015/12/28',DATE)-1)/14) AS watch FROM(
SELECT * FROM item_feature )a)a WHERE watch=1)a WHERE days<=3
为什么是取得1,2,3,5,7,9,14天内的累计数据？而不是第1,2,3,5,7,9,14天的单独一天的数据
代码片段大概是这个样子：
SELECT a.* FROM(
SELECT a.,DATEDIFF('2015/12/14',DATE)AS days FROM(
SELECT a.,FLOOR((DATEDIFF('2015/12/28',DATE)-1)/14) AS watch FROM(
SELECT * FROM item_feature )a)a WHERE watch=1)a WHERE days<=3