Question

我有一个名为female的SQL视图，看起来像下面的

+----------+----------+--------+------+
| actor_id | movie_id | gender | year |
+----------+----------+--------+------+
|   528787 |   2      | M      | 1996 |
|   528788 |   2      | F      | 1952 |
|   528789 |   1      | M      | 2001 |
|   528790 |   3      | M      | 1994 |
|   528791 |   2      | F      | 2000 |
|   528791 |   3      | F      | 2004 |
|   528791 |   4      | F      | 2000 |
|   528791 |   5      | F      | 2001 |
|   528792 |   4      | F      | 1999 |
|   528792 |   6      | F      | 2000 |
+----------+----------+--------+------+

...等等

此处actor_id和movie_id形成唯一的组合。我需要找到所有只有女性演员才能参与的movie_id。这意味着我需要排除所有只有男性演员或男女演员都参与过的电影。

预期产量

+----------+----------+--------+------+
| actor_id | movie_id | gender | year |
+----------+----------+--------+------+
|   528791 |   4      | F      | 2000 |
|   528791 |   5      | F      | 2001 |
|   528792 |   4      | F      | 1999 |
|   528792 |   6      | F      | 2000 |
+----------+----------+--------+------+

请帮助我了解解决方案以及对此可能进行的查询。

抱歉，对于某些人来说，这似乎太明显了。

给出的答案不正确，因为我已经编写了一个python代码来交叉验证值，并且在那里我得到了18927的数量。

Answer 1

grep(paste(delete, collapse="|"), string, invert = TRUE, value = TRUE) #[1] "jklo" "mnop"浮现在脑海：

NOT EXISTS

如果只想要电影，而不想要原始行，那么我将使用聚合：

select f.*
from female f
where not exists (select 1
                  from female f2
                  where f2.movie_id = f.movie_id and f2.gender = 'M'
                 );

Answer 2

您可以尝试以下操作

SELECT * 
FROM   [female] 
WHERE  movie_id IN (SELECT movie_id 
                    FROM   [female] 
                    GROUP  BY movie_id 
                    HAVING Max(gender) = Min(gender) 
                           AND Max(gender) = 'F')

如果视图中有重复项，并且如果您不希望重复项出现在输出中，则可以尝试如下操作。

 SELECT distinct actor_id , movie_id , gender , year  
    FROM   [female] 
    WHERE  movie_id IN (SELECT movie_id 
                        FROM   [female] 
                        GROUP  BY movie_id 
                        HAVING Max(gender) = Min(gender) 
                               AND Max(gender) = 'F')

Answer 3

对“ M”性别使用“不在”：

SELECT * FROM `test_data` 
where movie_id 
NOT IN (SELECT movie_id from test_data where gender = 'M')

Answer 4

尝试一下

SELECT *
FROM female
WHERE gender='F'
AND movieId NOT IN (SELECT movieId FROM female WHERE gender='M');

在另一列中找到条件中所有列的值

4 个答案: