您的条件
OnlineUseage是左侧联接变得像内部联接。
将您的条件移至该
from子句会更好：
SELECt users.Name, users.ID, IFNULL(SUM(users.Minutes), 0) AS MinutesonlineFROM users LEFT JOIN onlineUseage ON OnlineUseage.ID = users.ID and OnlineUseage.Date >= '2016-01-01 00:00:00' AND OnlineUseage.Date <= '2016-12-31 23:59:59'WHERe users.ID IN (332,554,5764,11,556,.........)GROUP BY users.ID,users.NameORDER BY users.ID
