如何更新行

Question

我有两张这样的表： -

表A

CODE          DESC
----          ----
A001          BLACK
12AA          SOFT
B001          GREY
13SW          ANTIQUE
B011          BROWN
23WQ          HARD

表B

NO      MODEL         COLOR     FINISH
--      -----         -----     ------
01      QWER          A001      12AA
02      ASDF          B011      13SW
03      ZXCV          B001      12AA
04      POIU          A001      23WQ

我希望使用SQL获得这样的输出： -

NO      MODEL         COLOR     FINISH
--      -----         -----     ------
01      QWER          BLACK      SOFT
02      ASDF          BROWN      ANTIQUE
03      ZXCV          GREY       SOFT
04      POIU          BLACK      HARD

Answer 1

您需要针对table_a加入两次：

select b.no, b.model, a1.desc, a2.desc
  from table_b b 
 inner join table_a a1 on (b.color = a1.code)
 inner join table_a a2 on (b.finish = a2.code)

Answer 2

研究SQL join s：

select b.no, b.model, a1.desc as 'color', a.desc as 'finish' 
from tableb b
inner join tablea as a
on b.finish = a.code
inner join tabla as a1
on b.color = a1.code

此查询根据公共标识符（在此code中）“合并”两个表。

Answer 3

你在这里：）

SELECT TEMP1.NO,TEMP1.MODEL,TEMP1.COLOR,TEMP2.FINISH FROM 
(SELECT B.NO, B.MODEL, A.CODE,A.DESC AS COLOR FROM A,B WHERE A.CODE=B.COLOR)TEMP1,   
(SELECT B.NO, B.MODEL, A.CODE,A.DESC AS FINISH FROM A,B WHERE A.CODE=B.FINISH)TEMP2
WHERE TEMP1.NO=TEMP2.NO