SQL 查询仅显示最少行数

Question

我试图只显示属于具有最小类别总数的类别的汽车的成本值

这是我正在尝试使用的查询：

select model, VIN,cost
from stock

期望的输出：

Model -     VIN       - Cost
STI     XXXXXXXXXXXX    ,000

我知道 having 运算符可用于计算每种汽车的最小类别总数：

having count(distinct category)=(select min(count(category)) 
from stock group by category)

但我不确定如何实现这样的运算符

Answer 1

如果我没理解错的话，这个查询比看起来要复杂一些。使用子查询获取每个类别的计数，使用 window 函数获取最小计数。然后将其连接回原始数据：

select s.model, s.VIN, s.cost
from stock s join
     (select category, count(*) as cnt, min(count(*)) over () as mincnt
      from stock s
      group by category
     ) c
     on s.category = c.category and cnt = mincnt

Answer 2

with    cnt_stock as
        (
        select  count(*) over (partition by category) cat_cnt
        ,       model
        ,       category
        from    stock
        )
select  *
from    cnt_stock
where   cat_cnt = 
        (
        select  min(cat_cnt)
        from    cnt_stock
        )

Example at SQL Fiddle.

SQL 查询仅显示最少行数

SQL query display min count rows only

sql

count

min

oracle11g