从 SQL 查询结果中求和不相等并删除重复项

Question

我的基本查询：

SELECT project_id
       name
       stories_produced
       on_date
      FROM project_prod
      WHERE on_date IN ('2017-03-01', '2017-06-10')
      ORDER BY project_id

它可以让我得到这些输出：

输出示例：

id       name                   stories_produced        on_date
1042    project 1               1001 (wanted)           2017-03-01
1042    project 1               1801 (wanted)           2017-06-10
1568    project 2               355  (wanted)           2017-06-10
1405    project 3               1    (not wanted)       2017-03-10
1405    project 3               1    (not wanted)       2017-06-10

Obs：(id, on_date) 有一个限制，这意味着在特定日期总是只能有一个项目生产的记录。

重复的记录，具有相同的 id，并且在两个日期都存在并且具有不同生产值（需要）

单条记录，仅存在于其中一个日期（需要）

问题：*

重复的记录，具有相同的 ID，并且存在于两个日期并且具有相等生产值（不需要）

我当前的查询，需要更改

      select project_id 
        name 
        CASE
          WHEN max(stories_produced) - min(stories_produced) = 0    
          THEN max(stories_produced)
          ELSE max(stories_produced) - min(stories_produced)
        END AS 'stories_produced'
        from project_prod
      WHERE on_date IN ('2017-03-01', '2017-06-10')
      group by project_id;

输出示例：

id       name                   stories_produced        
1042    project 1               800 (wanted)
1568    project 2               355  (wanted)
1405    project 3               1    (not wanted)

CASE 目前不处理第三个约束（重复记录，具有相同的 id，并且存在于两个日期并且具有相等的生产值 （不想要） em>)

是否有任何可能的条件可以适应这种情况？

Answer 1

一个选项使用not exists 删除行具有相同id、存在于两个日期且具有相同生产值的行：

select
    p.project_id,
    p.name,
    p.stories_produced,
    p.on_date,
  from project_prod p
  where 
    on_date in ('2017-03-01', '2017-06-10')
    and not exists (
        select 1
        from project_prod p1
        where 
            p1.on_date in ('2017-03-01', '2017-06-10')
            and p1.on_date <> p.date
            and p1.id = p.id 
            and p1.stories_produced = p.stories_produced

    )
  order by project_id 

在 MySQL 8.0 中，您可以使用窗口函数：

select
    project_id,
    name,
    stories_produced,
    on_date,
from (
    select 
        p.*,
        min(stories_produced) over(partition by project_id) min_stories_produced,
        max(stories_produced) over(partition by project_id) max_stories_produced,
        count(*) over(partition by project_id) max_stories_produced cnt
    from project_prod p
    where on_date in ('2017-03-01', '2017-06-10')
) t
where not (cnt = 2 and min_stories_produced = max_stories_produced)
oder by project_id