the Java PO class has List,Map or other classes as members, and mybatis acts as the dao layer
such as
Class Student{
int id;
School school;
List<String> courses;
List<Teacher> teachers;
Map<String, List<Integer>> courseScores;
}
School TeacherPO
Design a table in mysql, how to design the corresponding fields of school, teachers,courses,courseScores? Do school and teacher use school_id, teacher_id foreign keys directly? What about courses, courseScores?
field name, you can do the field according to the words you can understand at a glance. This is not limited, and it is not recommended that you have no choice but to use foreign keys. The constraint is too strong, which will lead to problems or restrictions in your other operations.
teachers child table
courseScores, is converted to json and a field is saved.
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