Question

我希望选择的国家/地区的价值最高为＆＃39;价值＆＃39;对于一个＆＃39; grpid＆＃39;。也已经选择了＃Country;＃39;不应该考虑其他的＆＃39; grpid＆＃39;同时检查最大值。（即不应在结果中重复国家或grpid）

SQL Fiddle

的结果： 的

Country    grpid        Value           Row_number

US        49707        604456458         1
GB        5086         497654945         4 
CA        909          353500201         10
JP        231          198291290         15

Answer 1

我相信这是你正在寻找的：

SQL Fiddle

;with cte as 
(
  select 
      country,
      max(value) as MaxVal,
      min(row_number) as MinRow
  from test1
  group by Country
)
select 
  c.country,
  t.grpid,
  c.MaxVal,
  c.MinRow
from cte c
join test1 t
  on t.country = c.country 
  and t.value = c.MaxVal
  and t.row_number = c.MinRow
order by country, grpid

Answer 2

尝试此查询，

  WITH OrderedOrders AS
  (
     SELECT country,grpid,value,ROW_NUMBER() OVER(PARTITION BY country ORDER BY   country,value DESC) AS 'RowNumber' 
     FROM test1
  ) 
 select * from  OrderedOrders
 where RowNumber =1

Answer 3

请试试这个查询

select 
    country,
    value,
    grpid,
    count(*) 
from test1 
group by  
    country,
    value,
    grpid 
order by 
    country,
    value desc

如何在SQL中为每个组选择最大行

3 个答案: