千峰商城-springboot项目搭建-73-购物车列表数据库实现

二、数据库实现

SQL:

#根据用户id查询当前用户的购物车信息
SELECT c.*,p.product_name,i.url
FROM shopping_cart c 
INNER JOIN product p
INNER JOIN product_img i
ON c.product_id=p.product_id AND i.item_id=p.product_id
WHERE user_id=14 AND i.is_main=1;

实体类：

ShoppingCartVO ：

//新增productName，productImg属性
@Data
@AllArgsConstructor
@NoArgsConstructor
public class ShoppingCartVO {

    private Integer cartId;
    private String productId;
    private String skuId;
    private String userId;
    private String cartNum;
    private String cartTime;
    private BigDecimal productPrice;
    private String skuProps;
    
    private String productName;
    private String productImg;

    
}

三、接口实现

 1.接口定义查询方法：

ShoppingCartMapper ：

@Repository
public interface ShoppingCartMapper extends GeneralDAO {
    
    public List selectShopcartByUserId(int userId);
}

2.映射配置：

<?xml version="1.0" encoding="UTF-8"?>


  
    
    
    
    
    
    
    
    
    
  

  
    
    
    
    
    
    
    
    
    
    
    
    
  
  
  
    SELECT c.cart_id,
           c.product_id,
           c.sku_id,
           c.user_id,
           c.cart_num,
           c.cart_time,
           c.product_price,
           c.sku_props,
           p.product_name,
           i.url
    FROM shopping_cart c
    INNER JOIN product p
    INNER JOIN product_img i
    ON c.product_id=p.product_id 
    AND i.item_id=p.product_id
    WHERE user_id=#{userId} AND i.is_main=1;
  

 3.测试：

   @Autowired
    private ShoppingCartMapper shoppingCartMapper;

    @Test
    public void testShoppingCart(){
        List shoppingCartVOS = shoppingCartMapper.selectShopcartByUserId(1);
        System.out.println(shoppingCartVOS);
    }