从SQL查询中排除记录

Question

由于一个或多个owner_ids （例如，2，4，6），我想回列表resources.id链接到owners的owners_has_resources 。 没问题，我只需SELECT DISTINCT ohr.resources_id FROM owners_has_resources ohr WHERE ohr.owners_id IN (2,4,6);

现在我被卡住了。 我想返回与上面相同的resources.id列表，但排除那些也链接到未删除所有者（由owners.deleted!=true确定）的链接，其中未删除链接（由owners_has_resources.deleted!=true确定） owners_has_resources.deleted!=true ）

可以假设对于所有最初提供的owners_ids （例如2、4、6）， owners.deleted为true

例如，给定owners_ids 2和4，我应该返回resources_id 2和3。请注意，我要说的是deleted=TRUE表示已删除，但是由于已经发布了使用前一个答案的答案，因此我不会编辑问题。 相反，下面的真值表显示owner_not_deleted和resource_not_deleted 。

+-----------+-------------------+--------------+----------------------+
| owners_id | owner_not_deleted | resources_id | resource_not_deleted |
+-----------+-------------------+--------------+----------------------+
|         2 | FALSE             |            1 | TRUE                 |
|         2 | FALSE             |            2 | TRUE                 |
|         4 | FALSE             |            2 | TRUE                 |
|         4 | FALSE             |            3 | TRUE                 |
|         5 | TRUE              |            1 | FALSE                |
|         5 | TRUE              |            2 | TRUE                 |
|         7 | TRUE              |            2 | FALSE                |
+-----------+-------------------+--------------+----------------------+

owners
- id (INT PK)
- name, etc
- deleted (true/false)

resources
- id (INT PK)
- name, etc

owners_has_resources
- owners_id (INT PK REFERENCES owners.id)
- resources_id (INT PK REFERENCES resources.id)
- deleted (true/false)

Answer 1

关于什么

SELECT DISTINCT ohr.resources_id 
FROM owners_has_resources ohr 
JOIN owners o ON ohr.owners_id = o.id
WHERE ohr.owners_id IN (2,4,6)
AND (o.deleted = FALSE OR ohr.deleted = FALSE);

Answer 2

首先，选择所需的数据，然后仅在NOT EXISTS块中选择未删除的所有者未引用的数据

SELECT DISTINCT ohr.resources_id 
FROM owners_has_resources ohr 
JOIN owners o ON ohr.owners_id = o.id
WHERE ohr.owners_id IN (2,4,6)
AND NOT EXISTS (
    SELECT NULL FROM owners_has_resources ohr2 
    JOIN owners o2 ON ohr2.owners_id = o2.id
    WHERE ohr2.deleted=FALSE 
    AND o2.deleted=FALSE
    AND ohr.resources_id=ohr2.resources_id 
)

Answer 3

SELECT DISTINCT ohr1.resources_id
FROM owners_has_resources ohr1
LEFT OUTER JOIN owners_has_resources ohr2 ON ohr2.resources_id=ohr1.resources_id AND ohr2.deleted = TRUE
LEFT OUTER JOIN owners o ON o.id=ohr2.owners_id AND ohr2.deleted = TRUE
WHERE ohr1.owners_id IN (2,4,6) AND o.id IS NULL;

要么

SELECT DISTINCT ohr1.resources_id
FROM owners_has_resources ohr1
LEFT OUTER JOIN owners_has_resources ohr2 ON ohr2.resources_id=ohr1.resources_id
LEFT OUTER JOIN owners o ON o.id=ohr2.owners_id
WHERE ohr1.owners_id IN (2,4,6) AND o.id IS NULL AND ohr2.deleted = TRUE AND ohr2.deleted = TRUE;

对于一种方法是否比另一种方法更好的任何评论，我将不胜感激。