Question

myTable的：

DATE      NAME   POCKET1   POCKET2   LOCATION  
1/1/2010  john   5         30        home  
2/1/2010  John   4         10        school  
3/1/2010  john   2         20        mall

我需要帮助来查询myTable，以获得预期结果。我知道如何获得最高和最高平均，但不知道如何获得最新的LOCATION。

select NAME,max(POCKET1),avg(POCKET2) from myTable
where NAME = 'john' group by NAME;

预期结果：

NAME   max(POCKET1)   avg(POCKET2)   LatestLOCATION  
john   5              20             mall

Answer 1

按日期desc

获得前1名

select 
  NAME
  ,max(POCKET1)
  ,avg(POCKET2) 
  , (select location from mytable order by date desc limit 1) as Location
from myTable 
where NAME = 'john' group by NAME;

如果您想获得John的最新位置

   select 
      NAME
      ,max(POCKET1)
      ,avg(POCKET2) 
      , (select location from mytable y where y.name = x.name order by date desc limit 1) as Location
    from myTable x
    where NAME = 'john' group by NAME;

如何执行查询以获取最新数据？

1 个答案: