加入兩個查詢到一個爲了加入結果

Question

我有一個小的SQL問題給你。

我有兩個疑問：

SELECT tbl_CostPrevisions.Month, SUM(tbl_CostPrevisions.Value) AS 'COST' FROM tbl_CostPrevisions 
WHERE tbl_CostPrevisions.Year = @YEAR 
GROUP BY tbl_CostPrevisions.Month 

SELECT tbl_IncomePrevisions.Month, SUM(tbl_IncomePrevisions.Value) AS 'INCOME' FROM tbl_IncomePrevisions 
WHERE tbl_IncomePrevisions.Year = @YEAR 
GROUP BY tbl_IncomePrevisions.Month 

給予的結果是這樣的：

1 48550,41 
2 61082,86 
3 49479,63 
4 46529,74 
5 46549,74 
6 48619,63 
7 49649,63 
8 48279,92 
9 48192,42 
10 48467,42 
11 48201,42 
12 48262,42 

而且

1 8123,16 
2 9174,15 
3 50009,12 
4 50705,00 
5 31971,00 
6 15217,00 
7 13151,00 
8 9677,00 
9 9616,00 
10 9653,00 
11 9698,00 
12 9605,00 

我怎麼能寫只是一個查詢，這將使我的以下結果？

1 48550,41 8123,16 
2 61082,86 9174,15 
3 49479,63 50009,12 
4 46529,74 50705 
5 46549,74 31971 
6 48619,63 15217 
7 49649,63 13151 
8 48279,92 9677 
9 48192,42 9616 
10 48467,42 9653 
11 48201,42 9698 
12 48262,42 9605 

感謝

Answer 1

嘗試以下內部聯接：

SELECT tbl_CostPrevisions.Month, SUM(tbl_CostPrevisions.Value) AS 'COST' , SUM(tbl_IncomePrevisions.Value) AS 'INCOME' 
FROM tbl_CostPrevisions 
INNER JOIN tbl_IncomePrevisions on tbl_CostPrevisions.Month = tbl_IncomePrevisions.Month 
WHERE tbl_CostPrevisions.Year = @YEAR AND tbl_IncomePrevisions.Year = @YEAR 
GROUP BY tbl_CostPrevisions.Month 

Answer 2

SELECT 
    tbl_CostPrevisions.Month, 
    SUM(tbl_CostPrevisions.Value) AS 'COST', 
    SUM(tbl_IncomePrevisions.Value) AS 'INCOME' 
FROM 
    tbl_CostPrevisions, 
    tbl_IncomePrevisions 
WHERE tbl_CostPrevisions.Year = @YEAR 
AND tbl_IncomePrevisions.Year = @YEAR 
AND tbl_CostPrevisions.Month = tbl_IncomePrevisions.Month 
GROUP BY 
    tbl_CostPrevisions.Month, 
    tbl_IncomePrevisions.Month 

Answer 3

嘗試下面的查詢。 tbl_IncomePrevisions上的INNER JOIN可以使用大量的數據。我已經把表格命名爲讓你更容易。

SELECT cp.Month, SUM(cp.Value) AS 'COST', SUM(ip.Value) AS 'INCOME' 
FROM tbl_CostPrevisions cp 
INNER JOIN tbl_IncomePrevisions ip ON ip.Month = cp.Month AND ip.Year = cp.Year 
WHERE cp.Year = @YEAR AND ip.Year = @YEAR 
GROUP BY cp.Month, ip.Month