以下是我的表结构的详细信息。
表结构“部门”:
id | department
1 | Department 1
2 | Department 2
3 | Department 3
4 | Department 4
表结构“custom_forms_departments”:
id | form_id | department_id | enduser_to_department | department_to_enduser
1 | 5 | 1 | Y | N
2 | 6 | 1 | N | Y
3 | 8 | 2 | Y | Y
4 | 7 | 3 | N | Y
5 | 4 | 3 | Y | N
6 | 2 | 4 | N | N
结果应返回 department_id,其在同一行或不同行中的字段“enduser_to_department”和“department_to_enduser”的值为“Y”。
department_id = 1 contatin value "Y"for "enduser_to_department"and "department_to_enduser"in different rows department_id = 2 contatin value "Y"for "enduser_to_department"and "department_to_enduser"in the same rows department_id = 3 contatin value "Y"for "enduser_to_department"and "department_to_enduser"in different rows
结果:
department_id | departments
1 | Department 1
2 | Department 2
3 | Deapartment 3
我正在使用以下未给出正确结果的 SQL 查询。
SELECT departments.department_id, departments.department
FROM custom_forms_departments , departments
WHERE departments.department_id = custom_forms_departments.department_id
AND (custom_forms_departments.enduser_to_department = 'Y'
OR custom_forms_departments.department_to_enduser = 'Y')
GROUP BY departments.department_id
ORDER BY departments.department_id DESC
请给我推荐这个。
最佳答案
首先尝试处理custom_forms_departments
。
方法:创建 2 个 custom_forms_departments
副本(c1 和 c2)。你会想加入他们,基于 (c1.department_id = c2.department_id
) - 简单,并且 (c1.enduser_to_department = c2.department_to_enduser
) - 因为你想要只获取同时包含“Y”的行(将过滤 WHEN 中的“Y”,但现在,您将获得在两列中具有相同值的任何行)。其次,使用 WHEN 仅过滤“Y”。
SELECT
custom_forms_departments.department_id
FROM
custom_forms_departments c1
INNER JOIN
custom_forms_departments c2 ON c1.department_id = c2.department_id
AND c1.enduser_to_department = c2.department_to_enduser
WHERE
c1.enduser_to_department = 'Y'
GROUP BY
c1.department_id
;
现在我们有了“复杂”的员工,让我们把所有人员聚集在一起并添加departments
列:
SELECT
departments.department_id, departments.department
FROM
departments
INNER JOIN
(SELECT
custom_forms_departments.department_id
FROM
custom_forms_departments c1
INNER JOIN custom_forms_departments c2 ON c1.department_id = c2.department_id
AND c1.enduser_to_department = c2.department_to_enduser
WHERE
c1.enduser_to_department = 'Y'
GROUP BY
c1.department_id) c3 ON departments.department_id = c3.department_id
;
关于mysql查询获取id不同列的记录,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/30388466/