《mybatis学习笔记（精编版）》由会员分享，可在线阅读，更多相关《mybatis学习笔记（精编版）（20页珍藏版）》请在金锄头文库上搜索。
1、实用文档第十六章回顾 SQL99中的连接查询1） 内连接2） 外连接3） 自连接第十七章回顾 hibernate多表开发1） 一对一2） 一对多3） 多对多第十八章mybatis一对一映射【学生与身份证】1）参见 2）创建 students.sql 和 cards.sqldroptablestudents; droptablecards; createtablecards(idint (5)primarykey , numvarchar (20);createtablestudents(idint (5)primarykey , namevarchar (10),cid int (5),con
2、straintcid_fkforeignkey (cid)referencescards(id);insertintocards(id,num ) values (1, 111 );.insertintostudents(id,name ,cid) values (1, 哈哈,1);3） 创建 Students.java 和 Card.java publicclassCard privateIntegerid ; privateStringnum ;privateStudentstudent; publicCard()publicInteger getId() returnid ;public
3、voidsetId(Integer id) this. id= id;publicString getNum() returnnum ;publicvoidsetNum(String num) this. num = num;publicStudent getStudent() returnstudent;publicvoidsetStudent(Student student) this. student= student;publicclassStudent privateIntegerid ; privateStringname ; privateCardcard; publicStud
4、ent()publicInteger getId() returnid ;publicvoidsetId(Integer id) this. id= id;publicString getName() returnname ;publicvoidsetName(String name) this. name = name;publicCard getCard() returncard;publicvoidsetCard(Card card) this. card= card;4） 创 建 StudentMapper.xml 和 CardMapper.xmlCardMapper.xml Stud
5、entMapper.xmlselect s.id,s.name,c.id,c.num from students s inner join cards c on s.cid = c.idand s.id = #id5） 创 建 StudentCardDao.javapublicclassStudentCardDao /*查询 1 号【学生】*/publicStudent findById(intid)throwsException SqlSession sqlSession =null;trysqlSession = MybatisUtil.getSqlSession(); returnsql
6、Session.selectOne(studentNamespace.findById,id); catch(Exception e) e.printStackTrace(); throwe; finallyMybatisUtil.closeSqlSession();publicstaticvoidmain(String args)throwsException StudentCardDao dao =new StudentCardDao();Student student = dao.findById(1);System.out .println(student.getId()+:+stud
7、ent.getName();System.out .println(student.getCard().getId()+:+student.ge tCard().getNum();第十九章mybatis一对多映射【班级与学生】1）参见 2）创建 grades.sql 和 students.sqldroptable students; droptable grades; createtable grades(gidint (5)primarykey , gnamevarchar (10);createtable students(sidint (5)primarykey , snamevarch
8、ar (10),sgidint (5),constraintsgid_fkforeignkey (sgid)referencesgrades(gid);insertintogrades(gid,gname)values (1,java );insertintostudents(sid,sname,sgid)values (1, 哈哈,1);insertintostudents(sid,sname,sgid)values (2, 呵呵,1);3） 创建 Grade.java 和 Student.sql/* 班级（单方）* authorAdminTC*/publicclassGrade priva
9、teIntegerid ;privateStringname ;privateListstudentList= new ArrayList(); publicGrade()publicInteger getId() returnid ;publicvoidsetId(Integer id) this. id= id;publicString getName() returnname ;publicvoidsetName(String name) this. name = name;publicList getStudentList() returnstudentList;publicvoids
10、etStudentList(List studentList) this. studentList= studentList;/* 学生（多方）* authorAdminTC*/publicclassStudent privateIntegerid ; privateStringname ; privateGradegrade; publicStudent()publicInteger getId() returnid ;publicvoidsetId(Integer id) this. id= id;publicString getName() returnname ;publicvoidsetName(String name) this. name = name;publicGrade getGrade() returngrade;publicvoidsetGrade(Grade grade) this. grade= grade;4） 创 建 GradeMapper.xml 和 StudentMapper.xml GradeMapper.xml! DOCTYPE mapperPUBLIC-
