SQL查询 - 连接表

Question

我在查询SQL方面很新，我需要一些帮助。我有2个表的信息：

表1：

Car# | Brand (ID) | Model (ID)
123  |      23    |     47

表2：

ID  | Description
23  |  Honda
47  |  Civic  

我需要执行一个提供输出的选择：

Car# | Brand (ID) | Model (ID)
123  |   Honda    |   Civic

有人可以帮助我。

非常感谢

Answer 1

你应该加入table2两次，如下所示

select t1.car, t2.Description as brand,t3.Description as model
from table1 t1
join table2 t2 on t2.id = t1.brand
join table2 t3 on t3.id = t1.model

Answer 2

您需要以下内容：

select car, 
(select description from table2 where ID = table1.brand), 
(select description from table2 where ID = table1.model) 
from table1

Answer 3

试试这个

WITH TABLE1 AS (SELECT '123' AS CAR, '23' AS BRAND, '47' AS MODEL FROM DUAL), TABLE2 AS (SELECT '23' AS ID, 'Honda' AS DESCRIPTION FROM DUAL UNION ALL SELECT '47' AS ID, 'Civic' AS DESCRIPTION FROM DUAL) SELECT A.CAR, B.DESCRIPTION, C.DESCRIPTION FROM TABLE1 A, (SELECT DESCRIPTION FROM TABLE2, TABLE1 WHERE BRAND = ID) B, (SELECT DESCRIPTION FROM TABLE2, TABLE1 WHERE MODEL = ID) C;