{"id":2847,"date":"2020-12-27T15:39:14","date_gmt":"2020-12-27T07:39:14","guid":{"rendered":"http:\/\/127.0.0.2\/?p=2847"},"modified":"2020-12-27T16:50:01","modified_gmt":"2020-12-27T08:50:01","slug":"2020java%e6%a1%86%e6%9e%b6%e6%95%99%e7%a8%8b%e4%b9%8bmybatis%e5%85%b3%e8%81%94%e5%85%b3%e7%b3%bb","status":"publish","type":"post","link":"https:\/\/www.9713job.com\/?p=2847","title":{"rendered":"2020java\u6846\u67b6\u6559\u7a0b\u4e4bmybatis\u5173\u8054\u5173\u7cfb"},"content":{"rendered":"

2020java\u6846\u67b6\u6559\u7a0b\u4e4bmybatis\u5173\u8054\u5173\u7cfb<\/h2>\n

1.\u4e00\u5bf9\u4e00<\/p>\n

\u6570\u636e\u5e93\u8868<\/strong>\uff1a<\/p>\n

create table member(#\u7528\u6237\r\n    uid int auto_increment primary key ,\r\n    username varchar(50) not null ,\r\n    sex varchar(2) not null\r\n)charset=utf8;\r\ncreate table resume(#\u7b80\u5386\r\n    id int auto_increment primary key ,\r\n    resume_name varchar(50) not null ,\r\n    resume_uid int unique ,\r\n    foreign key (resume_uid) references member(uid)\r\n)charset=utf8;<\/pre>\n
<\/p>\n
\"\"
\n\u5b9e\u4f53\u7c7b<\/strong>\uff1a<\/p>\n
public class Member {\r\n    private Integer uid;\r\n    private String username;\r\n    private String sex;\r\n    private Resume resume;<\/pre>\n
\u7b80\u5386\u5b9e\u4f53\u7c7b\uff1a<\/p>\n
public class Resume {\r\n    private Integer id;\r\n    private String resumeName;\r\n    private Integer resumeUid;\r\n    private Member member;<\/pre>\n
mapper<\/strong><\/p>\n
member\uff1a<\/p>\n
public interface MemberMapper {\r\n    Member selectMemberById(Integer uid);<\/pre>\n
resume\uff1a<\/p>\n
public interface ResumeMapper {\r\n    Resume selectResumeById(Integer id);<\/pre>\n
Membermapper.xml:<\/p>\n
<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\r\n<!DOCTYPE mapper PUBLIC \"-\/\/mybatis.org\/\/DTD Mapper 3.0\/\/EN\" \"http:\/\/mybatis.org\/dtd\/mybatis-3-mapper.dtd\" >\r\n<mapper namespace=\"mapper.MemberMapper\" >\r\n  <resultMap id=\"BaseResultMap\" type=\"entity.Member\" >\r\n    <id column=\"uid\" property=\"uid\" jdbcType=\"INTEGER\" \/>\r\n    <result column=\"uname\" property=\"username\" jdbcType=\"VARCHAR\" \/>\r\n    <result column=\"sex\" property=\"sex\" jdbcType=\"VARCHAR\" \/>\r\n    <association property=\"resume\" column=\"resume\" javaType=\"Resume\">\r\n      <id column=\"resume_id\" property=\"id\" jdbcType=\"INTEGER\" \/>\r\n      <result column=\"resume_name\" property=\"resumeName\" jdbcType=\"VARCHAR\" \/>\r\n      <result column=\"resume_uid\" property=\"resumeUid\" jdbcType=\"INTEGER\" \/>\r\n    <\/association>\r\n  <\/resultMap>\r\n  <select id=\"selectMemberById\" parameterType=\"int\" resultMap=\"BaseResultMap\">\r\n    select\r\n    member.uid uid,member.username uname,member.sex sex,resume.id resume_id,resume.resume_name resume_name,resume.resume_uid resume_uid\r\n    from member join resume on uid=resume_uid where uid=#{id}\r\n  <\/select>\r\n<\/mapper><\/pre>\n
\"\"
\n\u5728mybatis-config.xml\u6587\u4ef6\u6dfb\u52a0\u6ce8\u518c<\/strong><\/p>\n
<mapper resource=\"MemberMapper.xml\"\/><\/pre>\n
\u6d4b\u8bd5\uff1a<\/strong><\/p>\n
@Test\r\npublic void TestSelectMember(){\r\n    SqlSession ss = MybatisUtils.getSqlSession();\r\n    MemberMapper mapper = ss.getMapper(MemberMapper.class);\r\n    Member member = mapper.selectMemberById(1);\r\n    System.out.println(member);\r\n    System.out.println(member.getResume());\r\n}<\/pre>\n
\"\"<\/p>\n
2.\u4e00\u5bf9\u591a<\/h3>\n
\u6570\u636e\u5e93\uff1a<\/strong><\/p>\n
create table dept(#\u90e8\u95e8\r\n    id int primary key  auto_increment,\r\n    name varchar(50) ,\r\n    loc varchar(100)\r\n)charset=utf8;\r\ncreate table emp(#\u5458\u5de5\r\n    id int auto_increment primary key ,\r\n    name varchar(50),\r\n    salary double,\r\n    dep_id int ,\r\n    foreign key (dep_id) references dept(id)\r\n)charset=utf8;<\/pre>\n
\"\"
\n\u5b9e\u4f53\u7c7b\uff1a<\/strong><\/p>\n
Emp:<\/p>\n
public class Emp {\r\n    private Integer id;\r\n    private String name;\r\n    private Double salary;\r\n    private Integer depId;\r\n    private Dept dept;<\/pre>\n
Dept:<\/p>\n
public class Dept {\r\n    private Integer id;\r\n    private String name;\r\n    private String loc;\r\n    private List<Emp> empList;<\/pre>\n
 <\/p>\n
mapper\uff1a<\/strong><\/p>\n
DeptMapper\uff1a<\/p>\n
public interface DeptMapper {\r\n    Dept selectDeptById(Integer id);<\/pre>\n
 <\/p>\n
DeptMapper.xml\uff1a<\/strong><\/p>\n
<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\r\n<!DOCTYPE mapper PUBLIC \"-\/\/mybatis.org\/\/DTD Mapper 3.0\/\/EN\" \"http:\/\/mybatis.org\/dtd\/mybatis-3-mapper.dtd\" >\r\n<mapper namespace=\"mapper.DeptMapper\" >\r\n  <resultMap id=\"BaseResultMap\" type=\"entity.Dept\" >\r\n    <id column=\"dep_id\" property=\"id\" jdbcType=\"INTEGER\" \/>\r\n    <result column=\"name\" property=\"name\" jdbcType=\"VARCHAR\" \/>\r\n    <result column=\"loc\" property=\"loc\" jdbcType=\"VARCHAR\" \/>\r\n    <collection property=\"empList\" ofType=\"Emp\"><\/strong>\r\n      <id column=\"emp_id\" property=\"id\" jdbcType=\"INTEGER\" \/><\/strong>\r\n      <result column=\"emp_name\" property=\"name\" jdbcType=\"VARCHAR\" \/><\/strong>\r\n      <result column=\"salary\" property=\"salary\" jdbcType=\"DOUBLE\" \/><\/strong>\r\n      <result column=\"dep_id\" property=\"depId\" jdbcType=\"INTEGER\" \/><\/strong>\r\n    <\/collection><\/strong>\r\n  <\/resultMap>\r\n  <select id=\"selectDeptById\" parameterType=\"int\" resultMap=\"BaseResultMap\">\r\n    select\r\n    dept.id dep_id,dept.name,dept.loc,emp.id emp_id,emp.name emp_name,emp.salary\r\n    from dept join emp on dept.id=emp.dep_id where dept.id=#{id}\r\n  <\/select>\r\n<\/mapper><\/pre>\n
\"\"<\/p>\n
\u5728mybatis-config.xml\u6587\u4ef6\u6dfb\u52a0\u6ce8\u518c<\/strong><\/p>\n
<mapper resource=\"DeptMapper.xml\"\/><\/pre>\n
\u6d4b\u8bd5\uff1a<\/strong><\/p>\n
@Test\r\npublic void TestSelectDept(){\r\n    SqlSession ss = MybatisUtils.getSqlSession();\r\n    DeptMapper mapper = ss.getMapper(DeptMapper.class);\r\n    Dept dept = mapper.selectDeptById(2);\r\n    System.out.println(dept);\r\n    List<Emp> empList = dept.getEmpList();\r\n    for (Emp emp : empList) {\r\n        System.out.println(emp);\r\n    }\r\n}<\/pre>\n
\"\"
\n3.\u591a\u5bf9\u4e00<\/h3>\n
\u5229\u7528\u5458\u5de5\u7f16\u53f7\u67e5\u8be2\u90e8\u95e8<\/strong><\/p>\n
EmpMapper.xml\uff1a<\/p>\n
<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\r\n<!DOCTYPE mapper PUBLIC \"-\/\/mybatis.org\/\/DTD Mapper 3.0\/\/EN\" \"http:\/\/mybatis.org\/dtd\/mybatis-3-mapper.dtd\" >\r\n<mapper namespace=\"mapper.EmpMapper\" >\r\n  <resultMap id=\"BaseResultMap\" type=\"entity.Emp\" >\r\n    <id column=\"emp_id\" property=\"id\" jdbcType=\"INTEGER\" \/>\r\n    <result column=\"ename\" property=\"name\" jdbcType=\"VARCHAR\" \/>\r\n    <result column=\"salary\" property=\"salary\" jdbcType=\"DOUBLE\" \/>\r\n    <result column=\"dep_id\" property=\"depId\" jdbcType=\"INTEGER\" \/>\r\n    <association property=\"dept\" column=\"dept\" javaType=\"Dept\">\r\n      <id column=\"dept_id\" property=\"id\" jdbcType=\"INTEGER\" \/>\r\n    <result column=\"dept_name\" property=\"name\" jdbcType=\"VARCHAR\" \/>\r\n    <result column=\"loc\" property=\"loc\" jdbcType=\"VARCHAR\" \/>\r\n    <\/association>\r\n  <\/resultMap>\r\n  <select id=\"selectEmpById\" resultMap=\"BaseResultMap\" parameterType=\"int\">\r\n    select\r\n    emp.id emp_id,emp.name ename,emp.salary,emp.dep_id dep_id,dept.id dept_id,dept.name dept_name,dept.loc\r\n    from emp join dept on emp.dep_id=dept.id where emp.id=#{id}\r\n  <\/select>\r\n<\/mapper><\/pre>\n
\"\"<\/p>\n
\u6d4b\u8bd5<\/strong><\/p>\n
\"\"<\/p>\n
4.\u591a\u5bf9\u591a<\/h3>\n
\u6570\u636e\u5e93\u8868\uff1a<\/strong><\/p>\n
create table stu(#\u5b66\u751f\u8868\r\n    sid int auto_increment primary key ,\r\n    sname varchar(20) not null ,\r\n    sex varchar(2) not null\r\n)charset=utf8;\r\ncreate table subject(#\u79d1\u76ee\u8868\r\n    id int auto_increment primary key ,\r\n    subname varchar(20) not null\r\n)charset=utf8;\r\ncreate table stu_sub(#\u5b66\u751f\u548c\u79d1\u76ee\u5173\u8054\u8868\r\n    stu_id int ,\r\n    sub_id int ,\r\n    foreign key (stu_id) references stu(sid),\r\n    foreign key (sub_id) references subject(id),\r\n    primary key(stu_id,sub_id)\r\n)charset=utf8;<\/pre>\n
\"\"
\n\u5b9e\u4f53\u7c7b\uff1a<\/strong><\/p>\n
stu:<\/p>\n
public class Stu {\r\n    private Integer sid;\r\n    private String sname;\r\n    private String sex;\r\n    private List<Subject> subjects;<\/pre>\n
subject:<\/p>\n
public class Subject {\r\n    private Integer id;\r\n    private String subname;\r\n    private List<Stu> stus;<\/pre>\n
Mapper\uff1a<\/strong><\/p>\n
subjectMapper:<\/p>\n
public interface SubjectMapper {\r\n    Subject selectSubjectById(Integer id);<\/pre>\n
Mapper.xml\uff1a<\/strong><\/p>\n
subjectMapper.xml<\/p>\n
<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\r\n<!DOCTYPE mapper PUBLIC \"-\/\/mybatis.org\/\/DTD Mapper 3.0\/\/EN\" \"http:\/\/mybatis.org\/dtd\/mybatis-3-mapper.dtd\" >\r\n<mapper namespace=\"mapper.SubjectMapper\" >\r\n  <resultMap id=\"BaseResultMap\" type=\"entity.Subject\" >\r\n    <id column=\"id\" property=\"id\" jdbcType=\"INTEGER\" \/>\r\n    <result column=\"subname\" property=\"subname\" jdbcType=\"VARCHAR\" \/>\r\n    <collection property=\"stus\" ofType=\"Stu\">\r\n      <id column=\"sid\" property=\"sid\" jdbcType=\"INTEGER\" \/>\r\n      <result column=\"sname\" property=\"sname\" jdbcType=\"VARCHAR\" \/>\r\n      <result column=\"sex\" property=\"sex\" jdbcType=\"VARCHAR\" \/>\r\n    <\/collection>\r\n  <\/resultMap>\r\n  <select id=\"selectSubjectById\" resultMap=\"BaseResultMap\" parameterType=\"int\">\r\n    select<\/strong>\r\n        subject.id,subject.subname,stu.sid,stu.sname,stu.sex<\/strong>\r\n    from subject join stu_sub on subject.id=stu_sub.sub_id<\/strong>\r\n                 join mybatis.stu on stu_sub.stu_id = stu.sid<\/strong>\r\n    where subject.id=#{id}<\/strong>\r\n  <\/select>\r\n<\/mapper><\/pre>\n
\"\"
\n\u6d4b\u8bd5\uff1a<\/strong><\/p>\n
@Test\r\npublic void TestSelectSubject(){\r\n    SqlSession ss = MybatisUtils.getSqlSession();\r\n    SubjectMapper mapper = ss.getMapper(SubjectMapper.class);\r\n    Subject subject = mapper.selectSubjectById(1001);\r\n    System.out.println(subject);\r\n    List<Stu> stus = subject.getStus();\r\n    for (Stu stu : stus) {\r\n        System.out.println(stu);\r\n    }\r\n}<\/pre>\n
\"\"<\/p>\n
\"\"
\n\"\"<\/p>\n","protected":false},"excerpt":{"rendered":"
2020java\u6846\u67b6\u6559\u7a0b\u4e4bmybatis\u5173\u8054\u5173\u7cfb 1.\u4e00\u5bf9\u4e00 \u6570\u636e\u5e93\u8868\uff1a create table membe […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[],"class_list":["post-2847","post","type-post","status-publish","format-standard","hentry"],"_links":{"self":[{"href":"https:\/\/www.9713job.com\/index.php?rest_route=\/wp\/v2\/posts\/2847","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.9713job.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.9713job.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.9713job.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.9713job.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2847"}],"version-history":[{"count":12,"href":"https:\/\/www.9713job.com\/index.php?rest_route=\/wp\/v2\/posts\/2847\/revisions"}],"predecessor-version":[{"id":2866,"href":"https:\/\/www.9713job.com\/index.php?rest_route=\/wp\/v2\/posts\/2847\/revisions\/2866"}],"wp:attachment":[{"href":"https:\/\/www.9713job.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2847"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.9713job.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2847"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.9713job.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2847"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}