SQL Return 列值作为枚举 - 来自另一列的 GetValue() 字段

Question

这是两个表；

类别

----------------------------------------
Cathegory (tinyint)  |  Name (nvarchar)
----------------------------------------
0                    |  Field
1                    |  Mountain
2                    |  River
----------------------------------------

地点

------------------------------------------
Name (nvarchar)      |  Cathegory(tinyint)
------------------------------------------
Abc                  |  2
Xyz                  |  1
------------------------------------------

当我想检索 Places listing Names and their Cathegories not in the int format but according to the description in Cathegories.

所以检索 Abc 我想要这样；

"River" 而不是 '2'

Answer 1

您需要在 cathegory 上加入两个 table，如下所示。

select
    p.name as places,
    c.name as category_name
from places p
join cathegories c
on p.cathegory = c.cathegory

Answer 2

请使用以下查询，

select c.name as place, p.name as name from Cathegories c
inner join Places p
on (c.Cathegory  = p.Cathegory);

Answer 3

这是基于已接受答案的多个 JOIN 语句的版本：

SELECT 

ColumnUserViews,

C.Cathegory AS VCathegory, 

ColumnUserPoints, 

T.Description AS VTag1,
TT.Description AS VTag2


FROM dbo.Users U

JOIN dbo.Cathegories C ON U.Cathegory = C.Cathegory
JOIN dbo.Tags T ON U.Tag1 = T.Tag
JOIN dbo.Tags TT ON U.Tag2 = TT.Tag

关键字U定义物理table用户，T标签，TT也定义标签（可自由重命名）。 VCathegory 是一个新的要检索的虚拟列，它保存 Users.Cathegory 的值，根据当前方案转换为 Cathegories.Description（等效字符串）。

SQL Return 列值作为枚举 - 来自另一列的 GetValue() 字段

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