MyBatis注解(@)实现增删改查
Posted CaoPengCheng&
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MyBatis注解(@)实现增删改查
# crud
# 名称不一致
@Select("select * from book where id = #id")
@Results(
@Result(property="id",column="id",id=true),
@Result(property="name",column="b_name"),
@Result(property="createTime",column="b_create_time"),
@Result(property="price",column="price")
)
public Book findById(int id);
# 一对一
@Select("select * from chapter")
@Results(
@Result(property = "id", column = "id",id=true),
@Result(property = "name", column = "name"),
@Result(property = "bookId", column = "book_id"),
@Result(property = "book",column="book_id",one = @One(fetchType=FetchType.EAGER,select="com.zhiyou100.mapper.BookMapper.findById"))
)
public List<Chapter> findAll();
# 一对多
@Select("select * from book")
//解决数据库和java属性不一致
//property:java属性
//column:数据库属性
//id:判断是否是主键
@Results(
@Result(property="id",column="id",id=true),
@Result(property="name",column="b_name"),
@Result(property="createTime",column="b_create_time"),
@Result(property="price",column="price"),
@Result(property="chapters",column="id",many=@Many(fetchType=FetchType.EAGER,select="com.zhiyou100.mapper.ChapterMapper.findByBookId"))
)
public List<Book> findAll();
# 多对多
@Select("select * from user")
@Results(
@Result(property="id",column="id",id=true),
@Result(property="roles",column="id",many=@Many(fetchType=FetchType.EAGER,select="com.zhiyou100.mapper.RoleMapper.findByUserId"))
)
public List<User> findUserAndRole();
@Select("SELECT * from role r INNER JOIN user_role ur ON r.id = ur.role_id where ur.user_id = #userId")
public List<Role> findByUserId(int userId);
package com.prms.project.mapper;
import com.prms.project.domain.ProElement;
import org.apache.ibatis.annotations.*;
import java.util.List;
/**
* @author CaoPengCheng
* @version 1.0
* @date 2021/11/14 19:47
*/
@Mapper
public interface ProElementMapper
@Results(
@Result(property = "elementId", column = "element_id", id = true),
@Result(property = "elementName", column = "element_name"),
@Result(property = "orderNum", column = "order_num"),
@Result(property = "component", column = "component"),
@Result(property = "status", column = "status"),
@Result(property = "createBy", column = "create_by"),
@Result(property = "createTime", column = "create_time"),
@Result(property = "updateBy", column = "update_by"),
@Result(property = "updateTime", column = "update_time"),
@Result(property = "remark", column = "remark")
)
@Select("select element_id, element_name, order_num, component, status, create_time from prms_element order by order_num")
List<ProElement> selectElementList();
@Results(
@Result(property = "elementId", column = "element_id", id = true),
@Result(property = "elementName", column = "element_name"),
@Result(property = "orderNum", column = "order_num"),
@Result(property = "component", column = "component"),
@Result(property = "status", column = "status"),
@Result(property = "createBy", column = "create_by"),
@Result(property = "createTime", column = "create_time"),
@Result(property = "updateBy", column = "update_by"),
@Result(property = "updateTime", column = "update_time"),
@Result(property = "remark", column = "remark")
)
@Select("select element_id, element_name, order_num, component, status, create_time " +
"from prms_element " +
"order by order_num" +
"where element_id = #element_id")
ProElement selectElementById(@Param("element_id") Long element_id);
@Insert("insert into prms_element(element_name,order_num,component,status,create_by,create_time) " +
"VALUES('#element_name',#order_num,'#component',#status,'#create_by','#create_time')")
int insertElement(
@Param("element_name") String element_name,
@Param("order_num") int order_num,
@Param("component") String component,
@Param("status") int status,
@Param("create_by") String create_by,
@Param("create_time") String create_time
);
@Update("UPDATE prms_element" +
"set element_name='#element_name'," +
"order_num=#order_num," +
"component='#component'," +
"status=#status," +
"update_by='#update_by'," +
"update_time='#update_time'" +
"where element_id = #element_id ")
int updateElement(
@Param("element_id") Long element_id,
@Param("element_name") String element_name,
@Param("order_num") int order_num,
@Param("component") String component,
@Param("status") int status,
@Param("update_by") String update_by,
@Param("update_time") String update_time
);
@Delete("delete from prms_element where element_id = #element_id")
int deleteElementById(@Param("element_id") Long element_id);
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