MyBatis | SELECT Queries | Get Multiple Results

Source Code

sample_mapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
  PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
  "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="sample.mybatis">
  <select id="selectTest" resultType="map">
    select * from test_table
  </select>
</mapper>

Main.java

package sample.mybatis;

import java.io.InputStream;
import java.util.List;
import java.util.Map;

import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

public class Main {

    public static void main(String[] args) throws Exception {
        try (InputStream in = Main.class.getResourceAsStream("/mybatis-config.xml")) {
            SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(in);

            try (SqlSession session = factory.openSession()) {
                List<Map<String, Object>> result = session.selectList("sample.mybatis.selectTest");
                System.out.println(result);
            }
        }
    }
}

Execution Result

[{id=1, value=fizz}, {id=2, value=buzz}]

Explanation

  • SQL for retrieval is declared with the <select> tag.
    • Set the id attribute to the name used to reference this SQL.
    • Use the resultType attribute to define how each record in the query result is mapped.
    • Since map is specified here, each record is converted to a Map.
  • When a query result returns multiple records, use the selectList() method of SqlSession.
    • The return value is a List.