表关系/设计问题 [英] Table relationship/Design problem
问题描述
我有6张桌子
-tblStudents_info（包括学生姓名，地址等等）
-tblStudent_Classes（包括学生班级和流程）
-tblStudent_Subjects（包括基于特定组合的学生子喷射。）
-tblStudent_Marks（包括各种科目的学生分数）
-tblExam_Name（包括examID，Exam_Name）
-tblExam_Period（包括PeriodID，Period_Name）
问题来自于如何将表格关联（tblStudent_Marks，tblExam_Name和tblExam_Period）在每个时期（3个时期）完成的考试
i have 6 tables
-tblStudents_info( includes students names,address..etc)
-tblStudent_Classes(includes students classes and streams)
-tblStudent_Subjects(includes students subjets based on a certain combination.)
-tblStudent_Marks(includes student marks in various subjects)
-tblExam_Name(includes examID,Exam_Name)
-tblExam_Period(inclues PeriodID,Period_Name)
problem comes in how do i relate the tables (tblStudent_Marks,tblExam_Name and tblExam_Period)in the case where there are 3 Exams done in each period(3 periods)
推荐答案
在不知道如何设置tblStudent_Marks的情况下，很难建议如何关联表格。但是，如果表格设置得像我一样，tblStudent_Marks将是tblStudents_Info和tblExam_Name之间的连接表，这意味着每个学生/考试组合都会有一个单独的记录。由于我无法想到将考试时间直接与学生联系起来的原因，我会将tblExam_Name与tblExam_Period作为一对多关系，将一个Exam_Period外键添加到tblExam_Name，以确定考试在哪个时期发生了。
Without knowing how tblStudent_Marks is setup, it is difficult to suggest how to relate the tables. However, If the tables were setup like I would do it, tblStudent_Marks would be a join table between tblStudents_Info and tblExam_Name meaning that there would be a separate record for each student/exam combination. Since I can''t think of a reason to directly relate the exam period to the student, I would relate tblExam_Name to tblExam_Period as a one-to-many relationship by adding a Exam_Period foreign key to tblExam_Name to identify in which period the exam is taking place.
感谢Seth，我已经在下面的链接中发布了整个设计，以便清楚地了解我的意思。
最受关注的部分是：关系PartB
关系PartB-
thanks Seth, I have posted the whole design in the below links for a clear picture of what i mean.
the part with most concern is:relationship PartB
relationship PartB-
我看不到图片。请尝试解释图片提供的信息。
I can''t see the pictures. Please try to just explain what information the pictures would provide.
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