a:focus {
outline: thin dotted #333;
outline: 5px auto -webkit-focus-ring-color;
outline-offset: -2px;
}
a:hover {
outline: 0;
}
a:active {
outline: 0;
}
a:hover {
color: #005580;
text-decoration: underline;
}
blockquote small:before {
content: ‘\2014 \00A0‘;
}
q:before {
content: "";
}
q:after {
content: "";
}
blockquote:before {
content: "";
}
blockquote:after {
content: "";
}
mybatis批量保存
mybatis
批量保存
1、概述
mybatis 批量保存的时候，如果数据大于1000条，应该使用批量的形式进行处理数据；处理的不同的地方主要是在xml文件当中的配置信息；一种是使用java的for进行保存，另一种，是使用xml中的循环拼接sql来完成数据的插入；现在我们来对比两种方式的不同，以及执行效率；
2、 方法1：使用java的for循环来完成批量保存
1、打开批处理
session = sqlSessionFactory.openSession(ExecutorType.BATCH, true);
2、初始化数据
List<Student> preSaveStudent = initStudent();
3、执行批量插入
for (int i = 0; i < preSaveStudent.size(); i++) {
studentMapper.insert(preSaveStudent.get(i));
}
4、事务提交
session.commit();
代码实例：
@Test
public void BatchSave() throws IOException{
org.apache.ibatis.logging.LogFactory.useStdOutLogging();
Reader reader = Resources.getResourceAsReader("mybatis-config.xml");
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder()
.build(reader);
reader.close();
SqlSession session = null;
//1、打开批处理
session = sqlSessionFactory.openSession(ExecutorType.BATCH, true);
StudentMapper studentMapper = (StudentMapper) session.getMapper(StudentMapper.class);
Map<String, Object> params = new HashMap<String,Object>();
List<Student> students = studentMapper.queryStudentAndTeacher(params);
//2、初始化数据
List<Student> preSaveStudent = initStudent();
Date first = new Date();
//3、执行批量插入
for (int i = 0; i < preSaveStudent.size(); i++) {
studentMapper.insert(preSaveStudent.get(i));
}
//4、事务提交
session.commit();
System.out.println("first quest costs:"+ (new Date().getTime()-first.getTime()) +" ms");
}
/**
* 打印学生信息
* @author thero
* @param students
*/
public void printStudent(List<Student> students){
for (Student student : students) {
System.out.println(student.getId() + student.getTeacher().getName());
}
}
/**
* 初始化参数；用于测试保存内容；
* @author thero
* @return List<Student>
* student集合内容
*/
public List<Student> initStudent(){
List<Student> students = new ArrayList<Student>();
for(int i = 0 ;i < 1000;i++){
Student student = new Student();
student.setGender("男"+i);
student.setGrade("100"+i);
student.setMajor("软件技术"+i);
student.setName("小哈哈"+i);
student.setSupervisorId(1);
students.add(student);
}
return students;
}
其中xml的配置内容为：
<insert id="insert" parameterType="com.cpp.core.common.entity.Student" >
insert into student (id, name, gender,
major, grade, supervisor_id
)
values (#{id,jdbcType=INTEGER}, #{name,jdbcType=VARCHAR}, #{gender,jdbcType=VARCHAR},
#{major,jdbcType=VARCHAR}, #{grade,jdbcType=VARCHAR}, #{supervisorId,jdbcType=INTEGER}
)
</insert>
程序完成插入执行的时间为：
first quest costs:3267 ms
2.1 相关日志输出
Logging initialized using 'org.apache.ibatis.logging.stdout.StdOutImpl' adapter.
PooledDataSource forcefully closed/removed all connections.
PooledDataSource forcefully closed/removed all connections.
PooledDataSource forcefully closed/removed all connections.
PooledDataSource forcefully closed/removed all connections.
Openning JDBC Connection
Created connection 24166053.
Setting autocommit to true on JDBC Connection [[email protected]]
ooo Using Connection [[email protected]]
==> Preparing: SELECT s.id, s.`name`, s.gender, s.major, s.grade, s.supervisor_id , t.id as tea_id, t.`name` as tea_name, t.gender as tea_gender, t.research_area as tea_research_area, t.title as tea_title FROM student s LEFT JOIN teacher t ON s.supervisor_id = t.id
==> Parameters:
<== Columns: id, name, gender, major, grade, supervisor_id, id, name, gender, research_area, title
<== Row: 1, 李林, 男, 计算机科学与技术, 2011, 1, 1, 刘老师, null, null, null
<== Row: 2, 陈明, 男, 软件技术, 2012, 1, 1, 刘老师, null, null, null
<== Row: 4, 陈明2, 男, 软件技术, 2012, 2, 2, 郝老师, 男, 无语, 五
ooo Using Connection [[email protected]170bea5]
==> Preparing: insert into student (id, name, gender, major, grade, supervisor_id ) values (?, ?, ?, ?, ?, ? )
==> Parameters: null, 小哈哈0(String), 男0(String), 软件技术0(String), 1000(String), 1(Integer)
==> Parameters: null, 小哈哈0(String), 男0(String), 软件技术0(String), 1000(String), 1(Integer)
==> Parameters: null, 小哈哈1(String), 男1(String), 软件技术1(String), 1001(String), 1(Integer)
==> Parameters: null, 小哈哈2(String), 男2(String), 软件技术2(String), 1002(String), 1(Integer)
....
==> Parameters: null, 小哈哈999(String), 男999(String), 软件技术999(String), 100999(String), 1(Integer)
first quest costs:3267 ms
3、方法2 xml中循环学生的相关信息；
与方法1相比，在xml发生的变化较大的地方是xml,主要是在xml拼接了sql，下面是xml内容
<insert id="batchInsert" parameterType="list">
insert into student (id, name, gender,
major, grade
)
values
<foreach collection="list" item="item" index="index" separator=",">
(null,#{item.name},#{item.gender},#{item.major},#{item.grade})
</foreach>
</insert>
我们查看执行输入内容
Logging initialized using 'org.apache.ibatis.logging.stdout.StdOutImpl' adapter.
PooledDataSource forcefully closed/removed all connections.
PooledDataSource forcefully closed/removed all connections.
PooledDataSource forcefully closed/removed all connections.
PooledDataSource forcefully closed/removed all connections.
Openning JDBC Connection
Created connection 13676443.
Setting autocommit to true on JDBC Connection [[email protected]]
ooo Using Connection [[email protected]]
==> Preparing: SELECT s.id, s.`name`, s.gender, s.major, s.grade, s.supervisor_id , t.id as tea_id, t.`name` as tea_name, t.gender as tea_gender, t.research_area as tea_research_area, t.title as tea_title FROM student s LEFT JOIN teacher t ON s.supervisor_id = t.id
==> Parameters:
ooo Using Connection [[email protected]]
==> Preparing: insert into student (id, name, gender, major, grade ) values (null,?,?,?,?) , ..., (null,?,?,?,?)
==> Parameters: 小哈哈00-0(String), ..., 100999999-999(String)
耗费时间:257 ms
对比2中保存的方式，那么可以查看到保存的时间上的差别
方法1：first quest costs:3267 ms
方法2：耗费时间:257 ms
结论在使用批量保存的时候使用方法2进行保存的效率会有较大的提升
时间： 2024-08-30 17:30:15