我需要健身类的架构。
预订系统需要存储最多可以学习的学生数量,预定参加课程的学生人数,学生ID,日期时间等。
学生表需要存储他/她预订的课程。但如果我将学生ID存储在课堂表中,这可能就不需要了。
我希望得到一些好主意。
提前致谢。
答案 0 :(得分:1)
Student: ID, Name, ...
Class: ID, Name, MaxStudents, ...
Student_in_Class: STUDENT_ID, CLASS_ID, DATE_ENROLL
答案 1 :(得分:1)
*不是mySql大师,我通常会使用MS / MS,但我认为你会明白这一点。您可能需要在mySql文档中进行一些挖掘,以找到与我建议的数据类型相匹配的适当数据类型。另外,我只是简单解释了一些类型,以澄清它们的用途,因为这是mySql而不是MS SQL。
Class_Enrollment_ID INT IDENTITY PK ("identity is made specifically
to serve as an id and it's a field that the system will manage
on its own. It automatically gets updated when a new record is
created. I would try to find something similar in mySql")
Class_ID INT FK
Student_ID INT FK
Date_Time smalldatetime ("smalldatetime just stores the date as a
smaller range of years than datetime + time up to minutes")
Class_ID INT IDENTITY PK
Name VARCHAR('size') UNIQUE CONSTRAINT INDEX ("UNIQUE CONSTRAINT INDEX is
like a PK, but you can have more than one in a table")
Max_Enrollment INT ("unless you have a different max for different sessions
of the same class, then you only need to define max enrollment once per
class, so it belongs in the class table, not the Class_Enrollment table")
Student_ID INT IDENTITY PK
First_Name VARCHAR('size')
Last_Name VARCHAR('size')
Date_of_Birth smalldatetime ("smalldatetime can store just the date,
will automatically put 0's for the time, works fine")