在使用 GROUP BY 的同时为具有多个层的用户连接层?
Concating tiers for users with more than one tier, whilst using GROUP BY?
此查询选择以下内容:
SELECT jobs.JobID, school.School_Name,
CONCAT(staff.First_Name, ' ', staff.Last_Name) AS 'Full_Name',
staff.Phone_Number, role.Role
FROM jobs
INNER JOIN school ON jobs.SchoolID=school.SchoolID
INNER JOIN staff ON jobs.StaffID=staff.staffID
INNER JOIN role ON jobs.roleID=role.roleID
ORDER BY staff.StaffID asc
JOB ID FULL NAME ROLE
------ --------- ----------
1 BOB PRINCIPLE
2 BOB TEACHER
3 JACK TEACHER
4 SARAH ACCOUNTANT
5 SARAH NURSE
但是,我希望结果如下所示:
BOB PRINCIPLE, TEACHER
JACK TEACHER
SARAH ACCOUNTANT, NURSE
我对如何连接感到困惑,因为通过添加 GROUP BY 子句,它只选择第一个 JobID?
感谢任何帮助,谢谢。
您可以使用GROUP_CONCAT
SELECT Full_Name, GROUP_CONCAT(Role) AS Role
FROM
(
SELECT jobs.JobID, school.School_Name, CONCAT(staff.First_Name, ' ', staff.Last_Name)
AS Full_Name, staff.Phone_Number, role.Role
FROM jobs
INNER JOIN school ON jobs.SchoolID=school.SchoolID
INNER JOIN staff ON jobs.StaffID=staff.staffID
INNER JOIN role ON jobs.roleID=role.roleID
ORDER BY staff.StaffID asc
) q
GROUP BY Full_Name
此查询选择以下内容:
SELECT jobs.JobID, school.School_Name,
CONCAT(staff.First_Name, ' ', staff.Last_Name) AS 'Full_Name',
staff.Phone_Number, role.Role
FROM jobs
INNER JOIN school ON jobs.SchoolID=school.SchoolID
INNER JOIN staff ON jobs.StaffID=staff.staffID
INNER JOIN role ON jobs.roleID=role.roleID
ORDER BY staff.StaffID asc
JOB ID FULL NAME ROLE
------ --------- ----------
1 BOB PRINCIPLE
2 BOB TEACHER
3 JACK TEACHER
4 SARAH ACCOUNTANT
5 SARAH NURSE
但是,我希望结果如下所示:
BOB PRINCIPLE, TEACHER
JACK TEACHER
SARAH ACCOUNTANT, NURSE
我对如何连接感到困惑,因为通过添加 GROUP BY 子句,它只选择第一个 JobID?
感谢任何帮助,谢谢。
您可以使用GROUP_CONCAT
SELECT Full_Name, GROUP_CONCAT(Role) AS Role
FROM
(
SELECT jobs.JobID, school.School_Name, CONCAT(staff.First_Name, ' ', staff.Last_Name)
AS Full_Name, staff.Phone_Number, role.Role
FROM jobs
INNER JOIN school ON jobs.SchoolID=school.SchoolID
INNER JOIN staff ON jobs.StaffID=staff.staffID
INNER JOIN role ON jobs.roleID=role.roleID
ORDER BY staff.StaffID asc
) q
GROUP BY Full_Name