Mysql随机生成DataTime类型的数据

 随机生成2019年8，9，10月的时间

update table 
    set colum=
      concat('2019-',floor(8+rand()*3),'-',floor(1+rand()*28),' ', floor(rand()*24),':',floor(rand()*59),':',floor(rand()*59))

 随机生成上方数据间隔7天内的时间

update warehousing wa
set BufferZDate= (warehousingDate + 
    INTERVAL (concat(floor(rand()*7),' ',
    floor(rand()*24),':',floor(rand()*59),':',floor(rand()*59))) 
    DAY_SECOND
    )
where BufferZone='是';

根据操作时间判断操作工人属于哪一个班次（三班倒）

#根据时间判断操作工人属于哪一个班次
update warehousing  set ShiftTime=  
(case 
    when 
        time(WarehousingDate) between '06:00:00' and '13:59:59' 
            then 0  -- 白班
    when 
        time(WarehousingDate) between '14:00:00' and '21:59:59' 
             then 1  -- 中班
    when (
        (time(WarehousingDate) between '22:00:00' and '23:59:59')OR
        (time(WarehousingDate)    between '00:00:00' and '05:59:59')
        )     then 2  -- 夜班
end)