07-批处理

批处理

xml方式

批处理方式无法执行回写操作

<insert id="batchInsert" parameterType="java.util.List">
  insert into students(stu_name,stu_sex) values
  <foreach collection="list" item="item" index="index" separator=",">
    <!--cillection="list" 是MyBatis的强制要求，代表当前要遍历的集合-->
    <!--item属性指定当前迭代变量，index属性指定当前迭代索引-->
    <!--separator属性指定分隔符，MySQL插入多条数据时就是使用逗号进行分隔的所以指定逗号-->
      (#{item.stuName},#{item.stuSex})
  </foreach>
</insert>

<delete id="batchDelete" parameterType="java.util.List">
  delete from students where stu_id in
  <foreach collection="list" item="item" index="index" separator="," open="(" close=")">	<!--删除也是同理-->
    <!--open和close属性用于动态生成括号-->
      #{item}
  </foreach>
</delete>

用于测试关键代码片段，在创建sqlSession对象时需要将自动事务提交关闭，并手动提交和回滚，其他代码省略

/*批量新增*/
List<Student> students = new ArrayList<>();
for (int i = 0; i < 10; i++) {
  Student student = new Student();
  student.setStuName("张三" + i);
  students.add(student);
}
int number = sqlSession.insert("student.batchInsert", students);
sqlSession.commit();  //手动提交
System.out.println(number);	//查看影响条数

/*批量删除*/
List<Integer> stuIds = new ArrayList<>();
for (int i = 0; i < 10; i++) {
  stuIds.add(i);
}
number = sqlSession.delete("student.batchDelete", stuIds);
sqlSession.commit();  //手动提交
System.out.println(number);	//查看影响条数

注解方式

package com;

import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;

import java.util.List;

public interface StudentMapper {
  @Insert(
      "<script>" +  //使用script标签即可像xml中一样书写
          "insert into students(stu_name,stu_sex) values" +
          "<foreach collection='list' item='item' index='index' separator=','>" +
            "(#{item.stuName},#{item.stuSex})" +
          "</foreach>" +
      "</script>"
  )
  int batchInsert(List<Student> students);

  @Delete(
      "<script>" +  //使用script标签即可像xml中一样书写
          "delete from students where stu_id in" +
          "<foreach collection='list' item='item' index='index' separator=',' open='(' close=')'>" +
            "#{item}" +
          "</foreach>" +
      "</script>"
  )
  int batchDelete(List<Integer> stuIDs);
}

用于测试关键代码片段，在创建sqlSession对象时需要将自动事务提交关闭，并手动提交和回滚，其他代码省略

StudentMapper studentMapper = sqlSession.getMapper(StudentMapper.class);
/*批量新增*/
List<Student> students = new ArrayList<>();
for (int i = 0; i < 10; i++) {
  Student student = new Student();
  student.setStuName("张三" + i);
  students.add(student);
}
int number = studentMapper.batchInsert(students);
sqlSession.commit();  //手动提交
System.out.println(number);	//查看影响条数

/*批量删除*/
List<Integer> stuIds = new ArrayList<>();
for (int i = 0; i < 10; i++) {
  stuIds.add(i);
}
number = studentMapper.batchDelete(stuIds);
sqlSession.commit();  //手动提交
System.out.println(number);	//查看影响条数