mybati之parameterType传递多个参数

mybati之parameterType传递多个参数

 

mybati之parameterType传递多个参数

当在查询的时候需要传入多个参数的时候该怎么办呢:

1,封装成一个Model对象,底层HashMap还是一个

User user=new User();

user.setUserName("zhangsan");

user.setPassword("123456");

queryUserByuserNameAndPass(user);//为返回值类型为User

<select id="queryUserByuserNameAndPass"  resultType="User" parameterType="com.j1.User"  >

       select * from user u where u.user_name=#{userName} and u.pass_word=#{passWord}

</select>

2,使用HashMap封装

//使用HashMap定义:

HashMap <String,Object> map=new HashMap<String,Object>();

map.put("userName","zhangsan");

map.put("password","123456");

queryUserByuserNameAndPass(map);//为返回值类型为User

//sql 如下:

<select id="queryUserByuserNameAndPass"  resultType="User"  parameterType="Map" >

select * from user u where u.user_name=#{userName} and u.pass_word=#{passWord}

</select>

3,使用注解,@param

queryUserByuserNameAndPass(@param(''userName")String userName,@param("password")String password)

<select id="queryUserByuserNameAndPass"  resultType="User">

select * from user u where u.user_name=#{userName} and u.pass_word=#{passWord}

</select>

queryUserByuserNameAndPass(String userName,String PassWord);  //返回值类型为Usre
//sql

<select id="queryUserByuserNameAndPass"  resultType="User">
select * from user u where u.user_name=#{userName} and u.pass_word=#{passWord}//会报错的
</select>

<select id="queryUserByuserNameAndPass"  resultType="User">
select * from user u where u.user_name=#{0} and u.pass_word=#{1}//运行成功但是,可读性不高
</select>

//parameterType 参数类型可以是基本数据类型(int,String,long),可以是Model对象,也可以是Map;

1,基本数据类型:

@Override
public void deleteUserById(Long id) {
SqlSession sqlSession = sqlSessionFactory.openSession(true);
sqlSession.delete("cn.itcast.mybatis.user.deleteUserById", id);
}

//sql
<delete id="deleteUserById" parameterType="java.lang.Long">
      DELETE FROM tb_user WHERE id = #{id}
</delete>


2,Model对象

//java代码:
@Override
public void saveUser(User user) {
SqlSession sqlSession = sqlSessionFactory.openSession(true);
sqlSession.insert("cn.itcast.mybatis.user.saveUser", user);
}

@Override
public void updateUser(User user) {
SqlSession sqlSession = sqlSessionFactory.openSession(true);
sqlSession.update("cn.itcast.mybatis.user.updateUser", user);
}

//sql
<update id="updateUser" parameterType="cn.itcast.mybatis.pojo.User">
UPDATE tb_user
SET
password = #{password},
name = #{name},
age = #{age},
sex = #{sex},
birthday = #{birthday},
updated = NOW()
WHERE
id = #{id};
</update>

3.map

//java
HashMap <String,Object> map=new HashMap<String,Object>();
map.put("userName","zhangsan");
map.put("password","123456");
queryUserByuserNameAndPass(map);//为返回值类型为User

//sql 如下:

<select id="queryUserByuserNameAndPass"  resultType="User">

select * from user u where u.user_name=#{userName} and u.pass_word=#{passWord}//

</select>