如何從兩個表

Question

 tableA     tableB 
IdPrice  price    id   tax   IdPrice 
----------------------  ------------------------------------ 
    4   100    1   20    4 
------------------------  ------------------ ------------------ 
    5   150    2   10    6 
------------------------  ------------------ ------------------ 
    6   270    
------------------------ 
result = 
price id tax 
---- --- ---- 
100  1 20 
150  2 10 
270 null null 
my Query 
SELECT price,id,tax 
FROM tableB INNER JOIN 
tableA ON tableA.IdPrice= tableB.IdPrice 
but this result 

price id tax 
---- --- ---- 
100  1 20 
150  2 10 

Answer 1

SELECT 
    a.price as price, b.id as id, b.tax as tax 
FROM 
    tableA a 
LEFT OUTER JOIN 
    tableB b ON a.IdPrice = b.IdPrice 

使用左外選擇所有值加入你可以從表A中的所有記錄。