我正在尝试在一个名为“商品”的表中的单个查询中使用 GROUP
、 SORT
和 COUNT
。
这是我的 MySql
表的简化:
family sub_family name detailed_name
Agro Grains Wheat Wheat per 1 mt
Agro Grains Corn Corn per 1 mt
Agro Grains Sugar Sugar per 1 mt
Agro Fruits Apple Apple red
Agro Fruits Apple Apple green
Agro Fruits Apple Apple yellow
Agro Fruits Lemon Lemon classic
Wood Tree Lemon Lemon in logs
Wood Tree Oak Oak in logs
Wood Tree Epicea Epicea in logs
Wood Packaging Kraftliner Krafliner 3mm
我想 :
GROUP
由 name
SORT
由 family
, sub_family
和最后 name
COUNT
每个 family
、 sub_family
和 name
的行数(相同的 sub_family
)到目前为止,我设法在同一个
COUNT
中完成了除 sub_family
之外的所有工作。事实上,以下查询:
SELECT
TableC.family,
TableC.NbrFamily,
TableB.sub_family,
TableB.NbrSubFamily,
TableA.name,
TableA.NbrName
FROM
(
SELECT
family,
sub_family,
name,
COUNT(DISTINCT commodities.id) AS NbrName
FROM commodities GROUP BY name
) TableA
INNER JOIN
(
SELECT
sub_family,
COUNT(DISTINCT commodities.id) AS NbrSubFamily
FROM commodities GROUP BY sub_family
) TableB
ON (TableA.sub_family = TableB.sub_family)
INNER JOIN
(
SELECT
family,
COUNT(DISTINCT commodities.id) AS NbrFamily
FROM commodities GROUP BY family
) TableC
ON (TableA.family = TableC.family)
GROUP BY TableA.name
ORDER BY TableA.family,TableA.sub_family,TableA.name
结果如下:
family NbrFamily sub_family NbrSubFamily name NbrName
Agro 7 Grains 3 Wheat 1
Agro 7 Grains 3 Corn 1
Agro 7 Grains 3 Sugar 1
Agro 7 Fruits 4 Apple 3
Agro 7 Fruits 4 Lemon 2
Wood 4 Tree 3 Lemon 2
Wood 4 Tree 3 Oak 1
Wood 4 Tree 3 Epicea 1
Wood 4 Packaging 1 Kraftliner 1
您可以看到
NbrName
将 Lemon 计算了 2 次,但我希望它只计算 1 次,因为一个柠檬在 Fruits sub_family
中,另一个在 Tree sub_family
中。[更新]:这是我想要的结果:
family NbrFamily sub_family NbrSubFamily name NbrName
Agro 7 Grains 3 Wheat 1
Agro 7 Grains 3 Corn 1
Agro 7 Grains 3 Sugar 1
Agro 7 Fruits 4 Apple 3
Agro 7 Fruits 4 Lemon 1
Wood 4 Tree 3 Lemon 1
Wood 4 Tree 3 Oak 1
Wood 4 Tree 3 Epicea 1
Wood 4 Packaging 1 Kraftliner 1
最佳答案
只是我猜你要什么 http://sqlfiddle.com/#!9/e9206/16
因为它带来了想要的结果:
SELECT A.family, C.NbrFamily,A.sub_family,B.NbrSubFamily,A.name,COUNT(A.Name)
FROM commodities as A
LEFT JOIN (
SELECT family,sub_family,COUNT(Name) AS NbrSubFamily
FROM commodities
GROUP BY family,sub_family
) B
ON A.sub_family = B.sub_family
AND A.family = B.family
LEFT JOIN (
SELECT family,COUNT(Name) AS NbrFamily
FROM commodities
GROUP BY family
) C
ON A.family = C.family
GROUP BY A.family,A.sub_family,A.name
ORDER BY A.id
关于mysql - 在单个查询中分组、排序和计数,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/29680707/