Mybatis常用注解简介说明
下文笔者讲述MyBatis的常用注解简介说明,如下所示
注解 | 目标 | 对应的XML标签 |
@CacheNamespace | 类 | <cache> |
@CacheNamespaceRef | 类 | <cacheRef> |
@Results | 方法 | <resultMap> |
@Result | 方法 |
<result> <id> |
@One | 方法 | <association> |
@Many | 方法 | <collection> |
@Insert @Update @Delete | 方法 |
<insert> <update> <delete> |
@InsertProvider @UpdateProvider @DeleteProvider @SelectProvider | 方法 |
<insert> <update> <delete> <select> 允许创建动态SQL |
@Param | 参数 | N/A |
@Options | 方法 | 映射语句的属性 |
@select | 方法 | <select> |
@Select简单查询
@Select(" Select * from user ") @Results({ @Result(id = true, column = "id", property = "id"), @Result(column = "name", property = "name"), @Result(column = "tel", property = "tel"), @Result(column = "birth", property = "birth"), @Result(column = "address", property = "address") }) list<User> queryAllUser();
@Insert 简单插入
@Insert(" insert into user(name,sex,age) values(#{name},#{sex},#{age} " ) int saveUser(User user);
@Update 简单更新
@Update("update user set name= #{name} ,sex = #{sex},age =#{age} where id = #{id}") void updateUserById(User user);
@Delete 简单删除
@Delete("delete from user where id =#{id} ") void deleteById(Integer id);
@One
@Select(" select * from user where id = #{id} ") @Results( value = { @Result(column = "name",property = "name"), @Result(column = "type",property = "type", //one指示我们,查询出来的结果只有一个。 one = @One(select="com.xxxx.UserMapper.findTypeById", //及时加载 fetchType = FetchType.EAGER)) } ) User findUserById(Integer id);
@Many
@Select(" select * from dept") @Results({ @Result(id = true, column = "did", property = "did"), @Result(column = "name", property = "name"), @Result(column = "address", property = "address"), @Result(column = "id",property = "emps", //many指示我们,查询出来的结果有很多个 many = @Many( //select = sql语句 select = "com.xxxx.EmpMapper.findAllEmpByDid", //懒加载 fetchType = FetchType.LAZY)) }) List<Dept> findAllDept();
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