如何編寫一個帶數和組由共同的領域SQL兩個表

Question

我在SQL Server中的兩個表2008 R2：

Store:      Record: 
--------------    ------------------------ 
Shape  ID    PickedShape  Finished 
Circle  1    Circle   Y 
Circle  2    Circle   N 
Circle  3    Square   N 
Square  1    Square   N 
Square  2    Oval   Y 
Triangle 1    Oval   Y 

我想寫一個SQL查詢來輸出所有可能的形狀和它們的計數橫跨兩張桌子。我可以用愚蠢的方式寫出來，就像

select 
    'Circle', (select count(1) from Store where Shape = 'Circle'), 
    (select count(1) from Record where PickedShape = 'Circle'), 
    (select count(1) from Record where Finished = 'Y' and PickedShape = 'Circle') 
UNION 
select 
    'Square', (select count(1) from Store where Shape = 'Square'), 
    (select count(1) from Record where PickedShape = 'Square'), 
    (select count(1) from Record where Finished = 'Y' and PickedShape = 'Square') 
UNION... 

然後繼續，但那只是愚蠢而沒有效率。

我認爲一個更聰明的方法是使用group by。由於有些人可能不喜歡勺子餵養別人，所以這裏是我試過

SELECT 
    Shape, COUNT(Shape) AS Available, Picked, Finished 
FROM 
    Store 
FULL JOIN 
    (SELECT PickedShape, COUNT(1) As Picked, SUM(CASE WHEN Finished='Y' THEN 1 ELSE 0 END) AS Finished 
    FROM Record 
    GROUP BY PickedShape) t2 ON Store.Shape = t2.PickedShape 
GROUP BY 
    Shape, Picked, Finished 

和輸出

Shape Available Picked Finished 
NULL  0  2  2 
Circle  3  2  1 
Square  2  2  0 
Triangle 1  NULL NULL 

你可以看到問題所在。

首先，我想要在'形狀'下而不是NULL'橢圓形'。使用FULL JOIN爲我提供了兩個表中的所有變體，但沒有顯示它們...

其次，我希望Picked和Finished顯示0而不是NULL，表示缺少的變量。

第三，如果可能，我希望SQL更高效。

你如何解決這些問題？

謝謝！

Answer 1

我稍微修改了你的查詢 在第一個查詢中，按Shape分組，但'Oval'在第一個查詢中不存在。因此Shape從派生查詢中接收。三角不存在於派生查詢中，因此它的數量等於0.

SELECT 
    COALESCE(Shape, t2.PickedShape) AS Shape, COUNT(Shape) AS Available, 
    ISNULL(Picked, 0) AS Picked, ISNULL(Finished, 0) AS Finished 
FROM 
Store 
FULL JOIN 
    (SELECT PickedShape, COUNT(1) As Picked, SUM(CASE WHEN Finished='Y' THEN 1 ELSE 0 END) AS Finished 
    FROM Record 
    GROUP BY PickedShape) t2 ON Store.Shape = t2.PickedShape 
GROUP BY 
    Shape, t2.PickedShape, Picked, Finished