如何通过SQL JOIN从三个不同的表中追踪出值？

Question

我有如下 3 张桌子

table_1

securityno name    price
1           a11    12.12
2           z11    44.4

table_2

name      identifier Mainprice
a11_bond  NO34         11
z22_bond  NO98         22

table_3
securityno name    identifier 
1           a11    NO34         
2           z11    NO98         

我想检查

table_1

的价格是否正确。我只想显示来自

table_2

的输出

table_1

数据和

Mainprice

列。table_2

我正在尝试

select * from table_1 left join table_2 on table_3

使用3张桌子失败。

Answer 1

securityno name    price Mainprice
1           a11    12.12 11
2           z11    44.4  22

Answer 2

SELECT  
    t1.*,  
    t2.Mainprice  
FROM table_1 AS t1  
LEFT JOIN table_3 AS t3  
   ON t1.securityno = t3.securityno AND t1.name = t3.name  
INNER JOIN table_2 AS t2  
   ON t2.identifier = t3.identifier  

INNER JOIN

演示