我有3个与提交和研究员有关的表。
提交表:
SubmissionID, Type, Title, Status, Comment, CapturedOnRIMS, NumberOfAuthors, NumberOfWitsAuthors, TotalPages, PagesInPreamble, PagesInText, NumberOfChapters, Location, PublicationID, CESMID, SubmissionDate
研究员表:
ResearcherID, FirstName, Surname, RegistrationDate, QualificationType, JobName, Availability, SchoolID
ResearcherSubmission(关系表):
SubmissionID, ResearcherID
我正在尝试创建一个查询,显示每位研究人员提交的总数。研究人员可以提交许多文章,许多研究人员可以提交提交,因此可以进行关系表。
期望的输出:
Name Number of Submission
John Doe 14
William Smith 10
Ellie Carter 12
Susan Wright 10
答案 0 :(得分:1)
只需JOIN
表并执行group by
:
select r.FirstName, r.LastName, count(*) as no_of_sub
from Researcher r
join ResearcherSubmission rs on r.ResearcherID = rs.ResearcherID
join Submission s on s.SubmissionID = rs.SubmissionID
group by r.FirstName, r.LastName