根据2列过滤来自UNION结果的重复项

Question

我得到两个select查询的UNION，其中一个查询表是一个临时表以确保输出记录（所以临时表具有每个日期的预期输出但以0出售列的默认值

一个例子输出结果会是这样的：

ProductID | Product Desc | TransactionDate | Sale 
1011021 | SD DOG  | 2017-01-07  | 0 
1011021 | SD DOG  | 2017-01-07  | $17 
1011021 | SD DOG  | 2017-01-14  | 0 
1011021 | SD DOG  | 2017-01-14  | $15 
1011021 | SD DOG  | 2017-01-21  | $21 
1011021 | SD DOG  | 2017-01-28  | 0 
1011021 | SD DOG  | 2017-01-28  | $21 

联盟消除基于行的复制，我怎样才能让它在基于产品ID删除重复和transactionDate列，删除销售额为0的重复项？

--query下面

SELECT transactionProducts.productID, products.productDesc, sum(salePrice) as Sale, transactionDate 
FROM products LEFT JOIN transactionProducts on products.productID = transactionProducts.productID 
LEFT JOIN transactions ON transactionProducts.transactionID = transactions.transactionID 
LEFT JOIN productCategory on productCategory.productID = products.productID 
LEFT JOIN categories on categories.categoryID = productCategory.categoryID 
WHERE (transactionProducts.productID='123' AND transactions.transactionDate='2017-01-12' 
Group by transactionProducts.productID, transactionDate 
UNION select * from "temptable" group by productID, productDesc, Sale, transactionDate 
ORDER BY transactionDate 

Answer 1

使用not exists选择从临时表中尚未包含在结果集中的行：

. . . 
UNION ALL 
SELECT tt.* 
FROM temptable tt 
WHERE NOT EXISTS (SELECT 1 
        FROM transactionproducts tp JOIN 
         transaction t 
         ON t.transactionID = tp.transactionID 
        WHERE tp.productId = tt.productId AND 
         t.transactionDate = tt.transactionDate 
       ) 
GROUP BY productID, productDesc, Sale, transactionDate 
ORDER BY transactionDate 

Answer 2

如何：

SELECT transactionProducts.productID, products.productDesc, sum(salePrice) as Sale, transactionDate 
FROM products LEFT JOIN transactionProducts on products.productID = transactionProducts.productID 
LEFT JOIN transactions ON transactionProducts.transactionID = transactions.transactionID 
LEFT JOIN productCategory on productCategory.productID = products.productID 
LEFT JOIN categories on categories.categoryID = productCategory.categoryID 
WHERE (transactionProducts.productID='123' AND transactions.transactionDate='2017-01-12' 
      AND sum(salePrice) > 0) 
Group by transactionProducts.productID, transactionDate 
UNION select * from "temptable" group by productID, productDesc, Sale, transactionDate 
ORDER BY transactionDate 

注意，我添加了 “和SUM（salePrice）> 0” 的第一选择WHERE子句。

HTH