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.