mysql - 复杂条件连接

Question

Table B
PropertyID  Property
40      (old)  Retirement 
40      (old)  Retirement 
40      (old)  Retirement 
40      (old)  Retirement 
40      (old)  Retirement 

Table A

ProplistID  ProplistCode    ProplistName    PropertyID  PropertyCode PropertyName
101 evergree    Evergreen   30  453 Retirement Center
101 evergree    Evergreen   31  454 Retirement Community
101 evergree    Evergreen   32  443 Retirement Center
101 evergree    Evergreen   33  444 Retirement Community

我的查询

SELECT  t1.*, t2.PropertyCode 
FROM    Test.dbo.Table A T1 
        INNER JOIN Test.dbo.Table T2 ON T1.PropertyID = T2.ProplistID;

UNION ALL 

SELECT t1.*, t2.PropertyCode
FROM   Test.dbo.TABLE A T1
       INNER JOIN Test.dbo.TABLE B T2 ON T1.PropertyID = T2.PropertyID; 

ORDER BY 1

您好，我正在尝试进行这个复杂的连接。

我有两张 table

**

• 表 1

**

Col A   Col B
1       3
2           11
3           1
4           11
5           3
6           3
7           11

**

• 表 2

**

表2

Col A   Col B   Col C   Col D
1   Hello   3   Bye
2   Hello   4   Bye
5   Hello   6   Bye
7   Hello   11  Bye
8   Hello   12  Bye
9   Hello   13  Bye
20  Hello   14  Bye

我需要加入他们才能获得下面提到的表格

Col A   Col B   Col C
1   3   Hello
2   11  Hello
3   1   Bye
4   11  Bye
5   3   Hello
6   3   Bye
7   11  Hello

表 1 A 列有一些 ID 在 B 列中对应值为 3 或 11

表需要连接为

如果(表 1.Col A.Value = 3)

所以表 3.C 列 = 你好

然后加入(表 1.Col A = 表 2.Col A)

其他(表 1.Col A.Value = 3)

然后加入(表 1.A 列 = 表 2.C 列)

所以表 3.C 栏 = 再见

请帮我解决这个问题。

Answer 1

create table #t1 (ColA int,  ColB int)
insert #t1 values
(1,  3),
(2, 11),
(3,  1),
(4, 11),
(5,  3),
(6,  3),
(7, 11)

create table #t2 (ColA int,  ColB char(5), ColC int,  ColD char(3))
insert #t2 values
(1 ,  'Hello',   3 ,  'Bye'),
(2 ,  'Hello',   4 ,  'Bye'),
(5 ,  'Hello',   6 ,  'Bye'),
(7 ,  'Hello',   11,  'Bye'),
(8 ,  'Hello',   12,  'Bye'),
(9 ,  'Hello',   13,  'Bye'),
(20,  'Hello',   14,  'Bye')


select #t1.cola, #t1.colb, #t2.colb
from #t1
inner join #t2
on #t1.cola = #t2.cola 
union all
select #t1.cola, #t1.colb, #t2.cold
from #t1
inner join #t2
on #t1.cola = #t2.colc 
order by 1