Question

我的继承数据库存在问题，最初设置它的人只留下很少的文档。

我有一组用户，每个用户有三个潜在的职业。查询时，它返回如下值：

USER_ID CAREER_ID   TITLE
1       44           Agricultural Engineer
1       136          Educational Psychologist
1       132          Clinical Psychologist
18      245          3D Designer
18      2            Accountant - Private Practice
18      1            Accountant - Industry and Commerce
19      245          3D Designer
19      2            Accountant - Private Practice
19      1            Accountant - Industry and Commerce
20      128          Advice Centre Worker
20      130          Careers Adviser
20      129          Care Assistant
21      1            Accountant - Industry and Commerce
21      245          3D Designer
21      2            Accountant - Private Practice
23      245          3D Designer
23      2            Accountant - Private Practice
23      1            Accountant - Industry and Commerce
29      245          3D Designer
29      2            Accountant - Private Practice
29      1            Accountant - Industry and Commerce
30      219          PC Games Tester
30      173          Bouncer
30      103          Stunt Person
32      245          3D Designer
27      2            Accountant - Private Practice
27      1            Accountant - Industry and Commerce
27      245          3D Designer
30      219          PC Games Tester
30      173          Bouncer
30      103          Stunt Person

正如您所看到的，由于某种原因，职业1,2和245被设置为默认值。现在，我想过滤掉具有该特定职业集的用户，但不是所有用户的实例，因为任何用户都可以合法地选择一个或两个集合。

我可以过滤掉可能实际上有意选择那个特定集合的奇怪角色。

希望有人可以提供帮助。我确信解决方案很简单，但我无法想出来。

Answer 1

Select ...
From Occupations O
Where Not Exists    (
                    Select 1
                    From Occupations O1
                    Where O1.Career_Id In(1,2,245)
                        And O1.User_Id = O.User_Id
                    Group By O1.User_Id
                    Having Count(*) = 3
                    )

另一种解决方案：

Select ...
From Occupations O
Where Exists    (
                Select 1
                From Occupations O1
                Where O1.Career_Id Not In(1,2,245)
                    And O1.User_Id = O.User_Id
                )

上述解决方案的问题在于，它将排除那些只有少于三个默认职业的人。即，它将排除仅具有（1,2），（1,245），（2,245），（1），（2），（245）的用户。如果他们必须拥有全部三个而且只有那三个，那么你需要像这样修改这个解决方案：

Select ...
From Occupations O
Where Exists    (
                Select 1
                From Occupations O1
                Where O1.Career_Id Not In(1,2,245)
                    And O1.User_Id = O.User_Id
                )
Or Exists   (
            Select 1
            From Occupations O2
            Where O2.User_Id = O.User_Id
            Having Count(*) < 3
            )

Answer 2

我认为这应该确定列出了职业1,2和245的用户：

SELECT User_ID
  FROM Occupations
 WHERE Career_ID IN (1, 2, 245)
 GROUP BY Career_ID
HAVING COUNT(*) = 3

如果您想要那些没有这套职业的用户列表，那么：

SELECT User_ID
  FROM Occupations
 WHERE User_ID NOT IN
       (SELECT User_ID
          FROM Occupations
         WHERE Career_ID IN (1, 2, 245)
         GROUP BY Career_ID
        HAVING COUNT(*) = 3)

Answer 3

假设您有一个用户表，职业表和一个映射表（user_career_map），那么这将为您提供所需内容：

SELECT user_id, career_id, title
FROM (
  SELECT distinct m.user_id, m.career_id, c.title
    , sum(case when m.career_id in (1, 2, 245) then 1 else 0 end) over (partition by     m.user_id) filter
  FROM user_career_map m inner join career c on m.career_id = c.career_id
) WHERE filter <> 3
ORDER BY user_id, career_id;

如何在SQL中过滤特定的一组值，并且只过滤那个特定的集合？

3 个答案: