sqlsession.commit之后再做增删改,还能继续commit吗
时间: 2023-11-15 11:29:20 浏览: 57
可以,可以在 `commit()` 方法调用之后继续进行增删改操作,然后再次调用 `commit()` 方法提交事务。但是需要注意的是,每次调用 `commit()` 方法都会将当前会话中所有未提交的操作一起提交,所以建议在一个事务中完成所有的增删改操作,再调用一次 `commit()` 方法提交事务,避免产生不必要的问题。同时,也要注意在进行增删改操作时,需要确保操作的正确性和完整性,以避免数据异常和逻辑错误。
相关问题
mybatis 增删改
MyBatis 是一种优秀的持久化框架,它可以帮助我们更方便地进行数据库操作。下面是 MyBatis 中增删改的示例代码:
1. 插入数据
```java
// 创建一个 User 对象
User user = new User();
user.setName("Alice");
user.setAge(20);
// 插入数据
SqlSession sqlSession = sqlSessionFactory.openSession();
try {
UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
userMapper.insert(user);
sqlSession.commit();
} finally {
sqlSession.close();
}
```
2. 更新数据
```java
// 更新数据
SqlSession sqlSession = sqlSessionFactory.openSession();
try {
UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
User user = userMapper.getById(1);
user.setName("Bob");
userMapper.update(user);
sqlSession.commit();
} finally {
sqlSession.close();
}
```
3. 删除数据
```java
// 删除数据
SqlSession sqlSession = sqlSessionFactory.openSession();
try {
UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
userMapper.delete(1);
sqlSession.commit();
} finally {
sqlSession.close();
}
```
以上代码中,`UserMapper` 是一个 DAO 接口,它包含了常见的数据库操作方法。MyBatis 会根据接口定义自动生成相应的实现类。其中,`sqlSessionFactory` 是由 MyBatis 配置文件创建的工厂类。
新建员工表:id、name、age、address 1.完成员工表的增删改 2.完成查询所有员工,查询一个员工的方法 3.调用Mybatis完成员工增删改查Java
好的,下面是针对您的问题的回答。
1. 员工表的增删改操作:
增加员工:
```sql
INSERT INTO employee(id, name, age, address) VALUES (?, ?, ?, ?)
```
删除员工:
```sql
DELETE FROM employee WHERE id = ?
```
修改员工信息:
```sql
UPDATE employee SET name = ?, age = ?, address = ? WHERE id = ?
```
2. 查询所有员工和查询单个员工的方法:
查询所有员工:
```sql
SELECT * FROM employee
```
查询单个员工:
```sql
SELECT * FROM employee WHERE id = ?
```
3. 调用Mybatis完成员工增删改查Java:
首先,您需要创建一个Employee类,包含id、name、age和address属性,同时还需要在EmployeeMapper.xml中编写SQL语句,例如:
```xml
<!-- 增加员工 -->
<insert id="addEmployee" parameterType="Employee">
INSERT INTO employee(id, name, age, address) VALUES (#{id}, #{name}, #{age}, #{address})
</insert>
<!-- 删除员工 -->
<delete id="deleteEmployee" parameterType="int">
DELETE FROM employee WHERE id = #{id}
</delete>
<!-- 修改员工信息 -->
<update id="updateEmployee" parameterType="Employee">
UPDATE employee SET name = #{name}, age = #{age}, address = #{address} WHERE id = #{id}
</update>
<!-- 查询所有员工 -->
<select id="getAllEmployees" resultType="Employee">
SELECT * FROM employee
</select>
<!-- 查询单个员工 -->
<select id="getEmployeeById" parameterType="int" resultType="Employee">
SELECT * FROM employee WHERE id = #{id}
</select>
```
然后,在Java中调用Mybatis的方法:
```java
// 获取SqlSessionFactory
SqlSessionFactory sqlSessionFactory = MybatisUtils.getSqlSessionFactory();
// 获取SqlSession
SqlSession sqlSession = sqlSessionFactory.openSession();
// 获取Mapper
EmployeeMapper employeeMapper = sqlSession.getMapper(EmployeeMapper.class);
// 执行增加员工操作
Employee employee = new Employee();
employee.setId(1);
employee.setName("Tom");
employee.setAge(25);
employee.setAddress("Beijing");
employeeMapper.addEmployee(employee);
// 执行删除员工操作
employeeMapper.deleteEmployee(1);
// 执行修改员工信息操作
Employee employee = new Employee();
employee.setId(1);
employee.setName("Jerry");
employee.setAge(26);
employee.setAddress("Shanghai");
employeeMapper.updateEmployee(employee);
// 执行查询所有员工操作
List<Employee> employeeList = employeeMapper.getAllEmployees();
// 执行查询单个员工操作
Employee employee = employeeMapper.getEmployeeById(1);
// 提交事务
sqlSession.commit();
// 关闭SqlSession
sqlSession.close();
```
以上是一个简单的使用Mybatis进行员工表的增删改查的示例,希望能帮到您。