如何对行的相同值求和我有一个 table PURCHASE_ITEM ：

Question

"SELECT productID, qty, bill_date 
FROM purchase_item 
WHERE supplierID = 5 
GROUP BY purchase_itemID"


**1 400 2015-06-01
  2 100 2015-06-01
  3 200 2015-06-01
  5 150 2015-06-01
  2 110 2015-06-01   **

如何仅对常见产品 ID 的数量求和？

Answer 1

您可以将 SUM 函数用作

"Select SUM ('qty') as totalQty FROM purchase_item 
 WHERE supplierID = 5 
 GROUP BY purchase_itemID"

如何对行的相同值求和我有一个 table PURCHASE_ITEM ：

HOW to SUM same values of rows I have a table PURCHASE_ITEM :

mysql

sum

distinct