mybatis使用标签查询

1.基本查询

  @Select("select * from member where id=#{id}")
    public Member findById(String id) throws Exception;

2.一对一查询

  @Select("select * from orders")
    @Results({
            @Result(id = true, property = "id", column = "id"),
            @Result(property = "orderNum", column = "orderNum"),
            @Result(property = "orderTime", column = "orderTime"),
            @Result(property = "orderStatus", column = "orderStatus"),
            @Result(property = "peopleCount", column = "peopleCount"),
            @Result(property = "peopleCount", column = "peopleCount"),
            @Result(property = "payType", column = "payType"),
            @Result(property = "orderDesc", column = "orderDesc"),
            @Result(property = "product", column = "productId", javaType = Product.class, one = @One(select = "com.ssm.dao.IProductDao.findById")),
    })
    public List<Orders> findAll() throws Exception;

======实体
public class Orders {    
    private String id;
    private String orderNum;
    private Date orderTime;
    private String orderTimeStr;
    private int orderStatus;
    private String orderStatusStr;
    private int peopleCount;
    private Product product;
}
public class Product {
    private String id; // 主键
    private String productNum; // 编号 唯一
    private String productName; // 名称
    private String cityName; // 出发城市
    @DateTimeFormat(pattern="yyyy-MM-dd HH:mm")
    private Date departureTime; // 出发时间
    private String departureTimeStr;
    private double productPrice; // 产品价格
    private String productDesc; // 产品描述
    private Integer productStatus; // 状态 0 关闭 1 开启
    private String productStatusStr;
} 

3.一对多查询

 //多表操作
    @Select("select * from orders where id=#{ordersId}")
    @Results({
            @Result(id = true, property = "id", column = "id"),
            @Result(property = "orderNum", column = "orderNum"),
            @Result(property = "orderTime", column = "orderTime"),
            @Result(property = "orderStatus", column = "orderStatus"),
            @Result(property = "peopleCount", column = "peopleCount"),
            @Result(property = "peopleCount", column = "peopleCount"),
            @Result(property = "payType", column = "payType"),
            @Result(property = "orderDesc", column = "orderDesc"),
            @Result(property = "product", column = "productId", javaType = Product.class, one = @One(select = "com.ssm.dao.IProductDao.findById")),
            @Result(property = "member",column = "memberId",javaType = Member.class,one = @One(select = "com.ssm.dao.IMemberDao.findById")),
            @Result(property = "travellers",column = "id",javaType =java.util.List.class,many = @Many(select = "com.ssm.dao.ITravellerDao.findByOrdersId"))
    })
    public Orders findById(String ordersId) throws Exception;

==
  public class Orders {
    private String id;
    private String orderNum;
    private Date orderTime;
    private String orderTimeStr;
    private int orderStatus;
    private String orderStatusStr;
    private int peopleCount;
    private Product product;
    private List<Traveller> travellers;
    private Member member;
    private Integer payType;
    private String payTypeStr;
    private String orderDesc;
} 

4.添加和删除

  @Insert("insert into permission(permissionName,url) values(#{permissionName},#{url})")
    void save(Permission permission) throws Exception;


    @Delete("delete from role_permission where permissionId=#{id}")
    void deleteFromRole_Permission(String id) throws Exception;

    @Delete("delete from permission where id=#{id}")
    void deleteById(String id) throws Exception ;  
原文地址:https://www.cnblogs.com/liushisaonian/p/11208741.html