sql - 子查询与聚合函数混合

Question

我试图弄清楚这个查询，这让我很困惑。目标是创建一个 SQL 查询以显示：Scholarship_Name，Average Amount Awarded。我将链接下表以及我到目前为止所做的查询，希望有人能指出我做错了什么。

我想指出，这两个表没有任何共同的 PK 或 FK，所以这就是我以我的方式链接它们的原因。到目前为止，我在查询中所做的会显示名称，但是当我尝试平均它们的数量时，它们会变为 0.0 。我被难住了，整天都在谷歌上搜索。任何帮助，将不胜感激。

奖学金

ID/ SCHOLARSHIP_NAME / AMOUNT_AVAILABLE

"1" "Presidents Award"  "$15,000"

"2" "Chancellor Academic Award" "$25,000"

"3" "Chevron Award" "$20,000"

SCHOLARSHIP_AWARDS

ID / SCHOLARSHIP_ID / STUDENT_ID / AMOUNT_AWARDED

"1" "2" "9" "$1,500"

"2" "3" "8" "$1,500"

"3" "1" "7" "$2,000"

"4" "2" "6" "$1,500"

"5" "2" "5" "$3,000"

"6" "3" "4" "$5,000"

"7" "3" "3" "$2,500"

"8" "2" "2" "$2,500"

"9" "1" "1" "$1,500"

询问：

SELECT Scholarships.SCHOLARSHIP_NAME, AVG(Scholarship_Awards.Amount_Awarded) AS "Average Amount Awarded"
FROM Scholarships JOIN Scholarship_Awards
ON Scholarship_Awards.SCHOLARSHIP_ID = SCHOLARSHIPS.ID
GROUP BY SCHOLARSHIP_NAME

标签： sqlsubqueryaggregate-functions