mybatis: 返回主键ID(自增和非自增)

骑猪看日落 2022-05-23 10:05 446阅读 0赞

mapper映射文件

<?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="com.mybatis.mapper.TableNameMapper">
    	
    	<insert id="insertData" useGeneratedKeys="true" keyProperty="id">
    		insert into tableName values(null,#{name})
    	</insert>
    	
    	 <insert id="insertDataAgain">
    	 	
    	 	 
    	 	<selectKey resultType="integer" keyProperty="id" order="BEFORE">
    	 		SELECT LAST_INSERT_ID()
    	 	</selectKey>
    	 	
    		insert into tableName values(null,#{name})
    	</insert>
    </mapper>

mapper接口

public interface TableNameMapper { 
    	//插入数据
    	public Integer insertData(TableName tableName);
    	//插入数据
    	public Integer insertDataAgain(TableName tableName);
    }

测试代码:

InputStream inputStream = null;
    SqlSessionFactory sqlSessionFactory = null;
    SqlSession session = null;
    try { 
    	inputStream = Resources.getResourceAsStream("mybatis-config.xml");
    	sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
    	session = sqlSessionFactory.openSession();
    	TableNameMapper mapper = session.getMapper(TableNameMapper.class);
    	TableName tableName = new TableName();
    	tableName.setName("中文");
    	//插入数据方式1
    	//mapper.insertData(tableName);
    	//插入数据方式2
    	mapper.insertDataAgain(tableName);
    	session.commit();
    	System.out.println(tableName.getId());
    	
    } catch (IOException e) { 
    	e.printStackTrace();
    }finally { 
    	try { 
    		session.close();
    		inputStream.close();
    	} catch (IOException e) { 
    		e.printStackTrace();
    	}
    }

**`注: ORACLE返回主键最好是在插入SQL执行之前执行，也就是order属性值设置为before`**

<selectKey resultType="integer" keyProperty="id" order="AFTER">
    	 		SELECT EVE_SQU.nextval FROM dual
    </selectKey>
    <insert id="insertData" useGeneratedKeys="true" keyProperty="id">
    		insert into tableName values(#{id},#{name})
    </insert>