HAVING COUNT() 没有给出预期的结果

Question

正在尝试使用 distinct 获取 produce.prod_id 的重复值，但 clauses.but 未给出预期结果。

这是我的数据：

PRODUCE
--------- -----------
 PROD_ID   PROD_NAME
--------- -----------
  1         APPLES
  2         PEARS
  3         ORANGES
  4         BANANAS
  5         PEACHES


BUYERS
---------- ------------
 BUYER_ID   BUYER_NAME
---------- --------------
  1         ADAM BARR
  2         SEAN CHAI
  3         EVA CORETS
  4         ERIN O`MELIA


SALES
---------- --------- ------
 BUYER_ID   PROD_ID   QTY
---------- --------- ------
  1          2          15
  1          3           5
  4          1          37
  3          5          11
  4          3        1005

这是我的代码：

select produce.prod_name,
       buyer.BUYER_NAME,
       SALES.PROD_ID
  from produce
 inner join SALES on produce.PROD_ID = SALES.PROD_ID
 inner join buyer on SALES.BUYER_ID = buyer.BUYER_ID
 group by produce.prod_name,
          buyer.BUYER_NAME,
          SALES.PROD_ID
 having count(SALES.PROD_ID) > 1;

预期结果：

 PROD_Name   Buyer_Name
----------- --------------
 Oranges     ADAM BARR
 Oranges     ERIN O`MELIA

Answer 1

你不需要不同。你只需要 group by 和 having。您也不能按 buyer_name 分组以获得计数 > 1。这就是问题所在，您可以将其作为一组嵌套查询来执行此操作

select dupes.prod_name, 
buyers.buyer_name 
from (

    select produce.prod_name,
        SALES.PROD_ID,
        count(SALES.PROD_ID)
    from produce 
    inner join SALES on produce.PROD_ID=SALES.PROD_ID
    group by produce.prod_name, 
        SALES.PROD_ID
    having count(*)>1 
) as dupes
inner join sales on sales.prod_id = dupes.prod_id
inner join buyers on buyers.buyer_id = sales.buyer_id

Answer 2

您需要使用分析函数来满足您的要求

WITH PRODUCE(PROD_ID, PROD_NAME) AS (
 SELECT 1, 'APPLES' from dual union all
 select 2, 'PEARS' from dual union all
 select 3, 'ORANGES' from dual union all
 select 4, 'BANANAS' from dual union all
 select 5, 'PEACHES' from dual),
BUYERS (BUYER_ID, BUYER_NAME) as (
 select 1, 'ADAM BARR' from dual union all
 select 2, 'SEAN CHAI' from dual union all
 select 3, 'EVA CORETS' from dual union all
 select 4, 'ERIN O`MELIA' from dual),
SALES(BUYER_ID, PROD_ID, QTY) as (
 select 1, 2, 15 from dual union all
 select 1, 3, 5 from dual union all
 select 4, 1, 37 from dual union all
 select 3, 5, 11 from dual union all
 select 4, 3, 1005 from dual),
-- End of data preparation
TABLE_ AS (
  SELECT produce.prod_name,
         buyers.buyer_name,
         sales.prod_id,
         COUNT(1) OVER (PARTITION BY sales.prod_id) p_count
    FROM produce
   INNER JOIN sales
      ON produce.prod_id = sales.prod_id
   INNER JOIN buyers
      ON sales.buyer_id = buyers.buyer_id)
SELECT prod_name, buyer_name, prod_id
  FROM table_ 
 WHERE p_count > 1;

输出：

| PROD_NAME |   BUYER_NAME | PROD_ID |
|-----------|--------------|---------|
|   ORANGES | ERIN O`MELIA |       3 |
|   ORANGES |    ADAM BARR |       3 |

更新：您的简化查询将是：

With TABLE_ AS (
  SELECT produce.prod_name,
         buyers.buyer_name,
         sales.prod_id,
         COUNT(1) OVER (PARTITION BY sales.prod_id) p_count
    FROM produce
   INNER JOIN sales
      ON produce.prod_id = sales.prod_id
   INNER JOIN buyers
      ON sales.buyer_id = buyers.buyer_id)
SELECT prod_name, buyer_name, prod_id
  FROM table_ 
 WHERE p_count > 1;

Answer 3

这是我希望的简单答案。

这也是我的 SQL Fiddle 草稿本。 http://sqlfiddle.com/#!9/d80f6/3

select P.Prod_Name, Buyer_Name
from Sales S
join
   (select prod_id, count(prod_id) as ActSales
   from Sales group by prod_id having count(prod_id) > 1) SQ
on S.Prod_Id = SQ.Prod_Id
join Produce P
on S.Prod_Id = P.Prod_Id
join Buyers B
on S.Buyer_Id = B.Buyer_Id

HAVING COUNT() 没有给出预期的结果

HAVING COUNT() not giving out the expected result

sql

oracle

count

having-clause