Question

Pic of SCORE_T table我正在尝试找到一种方法，将平均价格编码到我从单独的表格建立的范围内。因此，我过去用来形成范围的点来自POINTS_T表，并且使用出现的次数通过使用COUNT（*）建立一列。我现在正在尝试查找每个范围的平均价格，但是我的价格在WINE表中，因为我在使用子查询并且不知道在哪里包含它，所以遇到了麻烦。我已经附上了两张图片，其中一张是我的原始代码没有错误（因为我没有尝试包括平均价格），第二张包括了我尝试将其包含在子查询中的内容。

这是我到目前为止的代码（不包括我尝试的平均价格）。

SELECT t.range as "Score Range", COUNT(*) as "Number of Occurrences" 
FROM (
  SELECT Case  
    when SCORE_T.Points between 95 and 100 then '95-100'
    when SCORE_T.Points between 90 and 94 then '90-94'
    when SCORE_T.Points between 85 and 89 then '85-89'
    when SCORE_T.Points between 80 and 84 then '80-84'
    end as RANGE
  FROM SCORE_T) t
GROUP BY t.range
ORDER BY COUNT(*) DESC
;

这就是我尝试的结果，这会产生错误。

SELECT t.range as "Score Range", COUNT(*) as "Number of Occurrences"
FROM (
  SELECT Case  
    when SCORE_T.Points between 95 and 100 then '95-100'
    when SCORE_T.Points between 90 and 94 then '90-94'
    when SCORE_T.Points between 85 and 89 then '85-89'
    when SCORE_T.Points between 80 and 84 then '80-84'
    end as RANGE, avg(WINE.Price) as "Average Price of Wine"
  FROM SCORE_T, WINE) t
GROUP BY t.range
ORDER BY COUNT(*) DESC
;

谢谢！

Answer 1

您需要一个JOIN，并且您正在使用avg()，而没有GROUP BY。我希望这样的事情：

SELECT sw.range as Score_Range,
       COUNT(*) as Number_of_Occurrences,
       AVG(sw.Price) as Average_Price
FROM (SELECT (Case when s.Points between 95 and 100 then '95-100'
                   when s.Points between 90 and 94 then '90-94'
                   when s.Points between 85 and 89 then '85-89'
                   when s.Points between 80 and 84 then '80-84'
              end) as RANGE,
           w.Price as Price
     FROM SCORE_T s JOIN
          WINE w
          ON s.? = w.?  -- what are the JOIN keys???
    ) sw
GROUP BY sw.range
ORDER BY COUNT(*) DESC;

?是链接得分和酒水表的列的占位符。

当我的价格位于Apex Oracle SQL的不同表中时，如何查找平均价格到分组范围内？

1 个答案: