【mybatis】＜foreach＞标签使用

利用 标签可以遍历迭代集合、数组元素，批量的执行增删命令。

mapper：

package com.atguigu.mybatis.mapper;
import org.apache.ibatis.annotations.Param;
public interface DynamicSQLMapper {
    
    int deleteMoreByArray(@Param("eids") Integer[] eids);
}

-mapper.xml:

   

    
        delete from users where id in
        
            #{eid}
        

    

test

package com.atguigu.mybatis.test;

import com.atguigu.mybatis.mapper.DynamicSQLMapper;
//import com.atguigu.mybatis.mapper.UserMapper;
//import org.apache.ibatis.annotations.Mapper;
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.Test;

import java.io.IOException;
import java.io.InputStream;

public class DynamicSQLMapperTest {
    @Test
    public void testDeleMoreByArray() throws IOException {
        InputStream is = Resources.getResourceAsStream("mybatis-config.xml");
        SqlSessionFactoryBuilder sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder();
        SqlSessionFactory sqlSessionFactory= sqlSessionFactoryBuilder.build(is);
        SqlSession sqlSession = sqlSessionFactory.openSession(true);
        DynamicSQLMapper mapper = sqlSession.getMapper(DynamicSQLMapper.class);
        int result = mapper.deleteMoreByArray(new Integer[]{6,7,8});
        System.out.println(result);

    }
}

原先数据库一共7条数据

删除之后剩下5条数据