连接两个表并从一个表中获取一组值

jos*_*sei 2 mysql sql join

我有两张桌子:一张,桌子显示星期几和当天的汤。餐桌汤有一个可能的汤的列表。

+-----+------------+--------+
| id  | day        |id_soup |
+-----+------------+--------+
| 1   | Friday     | 1      |
| 2   | Saturday   | 1      |
| 3   | Sunday     | 2      |
+-----+------------+--------+

+-----+------------+
| id  | soup       | 
+-----+------------+
| 1   | potatoes   | 
| 2   | carrots    | 
| 3   | peas       |
+-----+------------+
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要获取星期五汤(字符串而不是 ID),我可以使用如下查询:

SELECT ma.id, ma.day, ma.id_soup, so.soup
FROM main ma, soup so
WHERE ma.id_soup = so.id
AND ma.id = 1
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我得到这样的东西(输出)

+-----+------------+---------+----------+
| id  | day        | id_soup | soup     |
+-----+------------+---------+----------+
| 1   | Friday     | 1       | potatoes |
+-----+------------+---------+----------+
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如果周五只提供一种汤,这很有效。

问题是周五将提供两种汤(土豆和豌豆 - 一系列汤)

我们需要另一张桌子吗?

编辑

+-----+---------+---------+
| id  | id_day  | id_soup |     
+-----+---------+---------+
| 1   | 1       | 1       |
| 2   | 1       | 2       |
| 3   | 2       | 2       |
| 4   | 2       | 3       |
| 5   | 3       | 1       |
| 6   | 3       | 3       |
+-----+---------+---------+
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是否可以在单个查询中获取除了主表的其他字段(id、day、id_soup)之外,还获取 soups 数组(土豆、豌豆)?

构造此查询的最佳方法是什么?

编辑:

期望的输出(仅用于说明):

+-----+------------+---------+------------------+
| id  | day        | id_soup | soup             |
+-----+------------+---------+------------------+
| 1   | Friday     | 1       | potatoes, peas   |
+-----+------------+---------+------------------+
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编辑

问题:如果期望的输出是这样的:

+-----+------------+-------------------+
| id  | day        | soup              |
+-----+------------+---------+---------+
| 1   | Friday     | potatoes, carrots |
+-----+------------+---------+---------+
| 2   | Saturday   | carrots, peas     |
+-----+------------+---------+---------+
| 3   | Sunday     | potatoes, peas    |
+-----+------------+---------+---------+
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Sim*_*mon 6

是的,如果每天有多种汤,您将需要一张中间桌。GROUP_CONCAT您可以在声明中使用一天的所有汤SELECT

http://dev.mysql.com/doc/refman/5.7/en/group-by-functions.html#function_group-concat

SELECT ma.id, ma.day, GROUP_CONCAT(DISTINCT so.soup) as soup
FROM main ma
LEFT JOIN soupmain sm ON(ma.id = sm.id_main)
LEFT JOIN soup so ON(so.id = sm.id_soup)
WHERE ma.id = 1
GROUP BY ma.id
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