MyBatis入门之增删改查+数据库字段和实体字段不一致问题处理方法

SELECT id,user_name as name,sex,age from person

  SELECT id,user_name as name,sex,age from person

 
 
  
  
  
  
 
 
 
 
  SELECT * from person
 
 
 
  SELECT * FROM person WHERE id = #{id}
 

 
  INSERT INTO person(id,user_name,age,sex) VALUES(#{id},#{name},#{age},#{sex})
 

import com.luogg.domain.Person;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Before;
import org.junit.Test;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
/**
 * Created by luogg on 2017/2/17.
 */
public class TestMybatis {
 //SqlSessionFactory为线程安全的
 private SqlSessionFactory factory;
 @Before
 public void init() throws IOException {
  String resource = "sqlMapConfig.xml";
  InputStream is = Resources.getResourceAsStream(resource);
  factory = new SqlSessionFactoryBuilder().build(is);
 }
 @Test //查询所有
 public void findAll() throws IOException {
  /**
   * 测试数据库的连接
   * 1.定义一个String类型的变量resource,指向刚才配置的连接数据库的xml文件
   * 2.创建一个输入流,来读取我们的数据库配置文件
   * 3.输入流创建工厂.
   * 4.有了工厂之后open工厂
   * 5.通过session访问配置文件中的sql语句
   */
  SqlSession session = factory.openSession();
  //如何访问PersonMapper.xml中的sql语句呢&＃63; 命名空间+ .id
  List list = session.selectList("com.luogg.mapper.PersonMapper.find");
  System.out.println(list.size());
  for(Person p : list){
   System.out.println(p);
  }
 }
 @Test //通过ID查询人员信息
 public void selById(){
  SqlSession session = factory.openSession();
  Person p = session.selectOne("com.luogg.mapper.PersonMapper.selById",1);
  System.out.println(p);
 }
 @Test //添加人员信息
 public void add(){
  SqlSession session = factory.openSession();
  Person p = new Person();
  p.setId(4);
  p.setName("luogg");
  p.setAge(22);
  p.setSex(1);
  int i = session.insert("com.luogg.mapper.PersonMapper.insert",p);
  session.commit();
  if(i==1){
   System.out.print("添加人员成功");
  }
 }
}

 
  UPDATE person SET user_name=#{name},age=#{age} WHERE id=#{id}
 
 
 
  SELECT COUNT(*) FROM person
 

@Test //修改人员信息
 public void updatePer(){
  SqlSession session = factory.openSession();
  Person p = new Person();
  p.setId(4);
  p.setName("luoggg");
  //p.setSex(1);
  p.setAge(23);
  int i = session.update("com.luogg.mapper.PersonMapper.update",p);
  session.commit();
  if(i==1){
   System.out.print("修改信息成功");
  }
 }
 @Test //查询总的记录条数
 public void selCount(){
  SqlSession session = factory.openSession();
  int i = session.selectOne("com.luogg.mapper.PersonMapper.count");
  System.out.println(i);
 }

 
  SELECT  FROM person
  where user_name like #{name}
  AND sex=#{sex}
 
@Test //带条 件查询
 public void selByL(){
  SqlSession session = factory.openSession();
  Map map = new HashMap();
  map.put("name","luo%");
  map.put("sex",1);
  List list = session.selectList("com.luogg.mapper.PersonMapper.selByL",map);
  System.out.println(list.size());
  for(Person p : list){
   System.out.println(p);
  }
 }