如何在SQL中执行类似循环的操作以将数据从一个表复制到另一个表

I have a problem where I need to copy data from one database into another, I am never guaranteed to have the data available in realtime, and sometimes I might need to process 5 days' of data in one go etc. The processing day should operate over a period from 7am one day to 6:59am the next day, for example, between 2017-08-01 07:00 and 2017-08-02 06:59.I have a problem where I need to copy data from