hibernate之OneToMany和ManyToOne

hibernate一对多，多对一双向关联

假设一个老师对应多门课程，一门课程只对应一个老师

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@OneToMany(fetch=FetchType.LAZY,cascade={CascadeType.MERGE,CascadeType.REMOVE})@JoinColumn(name = "teacher_id")private Set<Course> courses = new HashSet<Course>();@ManyToOne(cascade={CascadeType.MERGE})@JoinColumn(name = "teacher_id",insertable=false,updatable=false)private Teacher teacher;

?这种方案得不到什么优化，反而会产生大量的update语句，推荐使用对一种方案

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