與總和合並的MySql表

Question

我這樣的twp表。

+----+--------+ +----------+-------+--------+ 
| id | fruit | | fruit_id | color | amount | 
+----+--------+ +----------+-------+--------+ 

結果爲：

SELECT 
    fruit,amount 
FROM 
    table1,table2 
WHERE fruit_id = id 

+--------+--------+ 
| fruit | amount | 
+--------+--------+ 
| Apple |  5 | 
| Apple |  5 | 
| Cherry |  2 | 
| Cherry |  2 | 
+--------+--------+ 

但我想這樣的結果：

+--------+--------+ 
| fruit | amount | 
+--------+--------+ 
| Apple |  10 | 
| Cherry |  4 | 
+--------+--------+ 

我該怎麼辦，懇求幫助我..
Thenks ...

Answer 1

您將使用聚合函數sum()和GROUP BY來獲取結果如下：

SELECT t1.fruit, sum(t2.amount) Total 
FROM table1 t1 
inner join table2 
    on t2.fruit_id = t1.id 
group by t1.fruit 

作爲一個提示，您應該使用標準ANSI連接語法和INNER JOIN。