Question

我有桌子：

+------------+
| Ingredient |
+------------+
| id         |
+------------+
| name       |
+------------+

+---------------+
| Relingredient |
+---------------+
| id_ingredient |
+---------------+
| id_recipe     |
+---------------+

+--------+
| Recipe |
+--------+
| id     |
+--------+
| name   |
+--------+

并且我需要选择具有我想要的成分的食谱（所有成分传递给他们）我试过这个：

SELECT R.id, R.nom FROM Recipe R, Relingredient RI, Ingredient I 
WHERE  R.id = RI.id_recipe AND RI.id_ingredient = I.id AND I.name='onion' AND I.name='oil' 
GROUP BY R.name

但重新调整零行

我也试过这个：

SELECT R.id, R.nom FROM Recipe R, Relingredient RI, Ingredient I 
WHERE  R.id = RI.id_recipe AND RI.id_ingredient = I.id AND (I.name='onion' or I.name='oil') 
GROUP BY R.name

但它会选择所有含有洋葱或油的食谱，而不仅仅是那些含有洋葱 AND 油的食谱......我该怎么办？

（编辑）我想要的样本：
例如我有食谱：
1：烤鸡（配料：鸡肉，洋葱，油）
2：中国汤（配料：猪肉，洋葱，油，面条）
3：蔬菜三明治（配料：面包，油，番茄，沙拉）
查询应该只返回食谱：烤鸡肉和中国汤

谢谢你的帮助!!

Answer 1

尝试这样的事情：

SELECT
  R.id, R.name
FROM Recipt R
  JOIN Relingredient RI
    ON R.Id = RI.Id_recipe
  JOIN Ingredient I
    ON RI.Id_ingredient = I.Id
WHERE I.name = 'onion'
    OR I.name='oil'
GROUP BY R.id, R.name
HAVING COUNT(I.name) = 2

Answer 2

试试这个：

SELECT R.id, R.name FROM Recipe R
       Where R.Id in (
                         Select RI.Id_recipe From Relingredient as RI 
                                INNER JOIN Ingredient as I ON  RI.Id_ingredient = I.Id
                                WHERE I.name = 'onion'
                                      OR I.name='oil'
                     )

我完全明白了。新查询：

SELECT  *
        FROM    dbo.Recipt
        WHERE   Id IN ( SELECT  id_recipe
            FROM    dbo.Relingredient
                    INNER JOIN dbo.Ingredient ON id_ingredient = Id
            WHERE   Name = 'oil' )
    AND Id IN ( SELECT  id_recipe
                FROM    dbo.Relingredient
                        INNER JOIN dbo.Ingredient ON id_ingredient = Id
                WHERE   Name = 'union' )

Answer 3

要获得您正在寻找的成分，请使用having条款：

SELECT R.id, R.nom
FROM Recipe R JOIN
     Relingredient RI
     ON R.id = RI.id_recipe JOIN
     Ingredient I 
     ON RI.id_ingredient = I.id
GROUP BY R.name
HAVING SUM(CASE WHEN I.name = 'onion' THEN 1 ELSE 0 END) > 0 AND
       SUM(CASE WHEN I.name = 'oil' THEN 1 ELSE 0 END) > 0 AND
       SUM(CASE WHEN I.name NOT IN ('onion', 'oil') THEN 1 ELSE 0 END) = 0;

having子句中的每个条件都会检查其中一个条件。首先检查至少一种成分是“洋葱”，第二种是至少一种是“油”，第三种是没有其他成分存在。如果你想允许其他成分，请删除最后一个条款。

这种方法对于成分的不同条件非常灵活。

编辑：

以下having子句允许您仅为配料命名一次。但您还需要插入计数：

HAVING COUNT(DISTINCT CASE WHEN I.name IN ('onion', 'oil') THEN I.name END) = COUNT(DISTINCT NAME) AND
       COUNT(DISTINCT NAME) = 2;

如果一个食谱不止一次包含一种成分，distinct就会出现。

具有复杂条件的多对多选择

3 个答案: