Teradata UNION和其他數據

Question

假設我們有兩個不同的表

Table_eBay

Id      Product      
 1      SomeProduct-1
 2      SomeProduct-2

Table_Amazon

Id      Product      
1       SomeProduct-1
2       SomeProduct-3

可以像下面這樣組合嗎？

表格輸出

Id      Product        isEbay       isAmazon
 1      SomeProduct-1  TRUE         TRUE
 2      SomeProduct-2  TRUE         FALSE
 3      SomeProduct-3  FALSE        TRUE

Answer 1

select      row_number () over (order by Product)                as Id
           ,Product
           ,max (case tab when 'E' then 'TRUE' else 'FALSE' end) as isEbay
           ,max (case tab when 'A' then 'TRUE' else 'FALSE' end) as isAmazon

from        (           select 'E' ,Product from Table_eBay 
            union all   select 'A' ,Product from Table_Amazon
            ) t (tab,Product)

group by    Product

order by    Product
;

Answer 2

我建議使用完全聯接，如下所示：

select 
case when AMZ.product is null then EB.product else AMZ.product end as product,
case when AMZ.id is null then 'FALSE' else 'TRUE' end as isEbay,
case when EB.id is null then 'FALSE' else 'TRUE' end as isAmazon,
rownum as ID /* alternative take the last char of product */
 from AMAZON AMZ FULL OUTER JOIN EBAY EB ON
AMZ.product = EB.product;

考慮到在您的示例中，產品ID = 2表示表中有2種不同的產品（我使用了Oracle的rownum）。

問候，塞爾吉奧