MySQL根据行数据获取结果列

时间:2016-05-04 11:54:05

标签: mysql

我有两张桌子。第一个包含水果:

+----+--------+
| id | fruit  |
+----+--------+
| 1  | banana |
+----+--------+
| 2  | orange |
+----+--------+

第二个包含每个篮子的水果量:

+----+--------+----------+--------+
| id | basket | fruit_id | amount |
+----+--------+----------+--------+
| 1  | a      | 1        | 5      |
+----+--------+----------+--------+
| 2  | a      | 2        | 10     |
+----+--------+----------+--------+
| 3  | b      | 1        | 8      |
+----+--------+----------+--------+
| 4  | b      | 2        | 12     |
+----+--------+----------+--------+

现在我想得到这样的东西。

+----------+----------+----------+
| fruit_id | basket_a | basket_b |
+----------+----------+----------+
| 1        | 5        | 8        |
+----------+----------+----------+
| 2        | 10       | 12       |
+----------+----------+----------+

显然,它必须适用于n个篮子。我非常乐意分享任何进展/代码,但不幸的是我不知道如何开始。谢谢你的理解。

2 个答案:

答案 0 :(得分:0)

select b.fruit_id,case when b.basket = 'a' then b.amount end as 'basket_a',
case when b.basket = 'b' then b.amount end as 'basket_b' from table 1 join table2 on table1.id = table2.id group by fruit_id;

请检查上面的查询,这是你想要的吗?

答案 1 :(得分:0)

拥有n列不是一个好主意。你真的希望你的结果是表格格式吗?

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