Question

在这里忍受我，我对SQL很新。我写了以下查询，但DISTINCT基本上被我的WHERE语句否定了。这是因为表格中的日期后跟一个时间戳，因此如果订单项的时间有任何差异，它会生成一个新行。

在日期之后完全忽略所有内容的最佳方法是什么，以便不会因时间戳而生成新行？根据我的发现，我认为使用GROUP BY可以更好地实现这一点，但接缝始终会产生错误（很可能我不知道在何处放置聚合函数）。

非常感谢任何帮助。谢谢！

Select DISTINCT
 so.num AS Ref
,  so.shiptoname AS Recipient_Full_Name
, so.shiptoaddress AS Address_1
, so.shiptocity AS City
, stateconst.name AS State
, so.shiptozip AS Zip
, so.billtoname AS Buyer_Name
, qbclass.name AS Class
, soitem.datescheduledfulfillment AS Fulfillment_Date
From SO
JOIN stateconst
ON so.shiptostateid=stateconst.id
JOIN qbclass
ON so.qbclassid=qbclass.id
JOIN soitem
ON so.id=soitem.soid
WHERE DATESCHEDULEDFULFILLMENT LIKE '2016-05-10%'

Answer 1

使用CAST()将datetime数据类型更改为date类型：

Select DISTINCT
 so.num AS Ref
,  so.shiptoname AS Recipient_Full_Name
, so.shiptoaddress AS Address_1
, so.shiptocity AS City
, stateconst.name AS State
, so.shiptozip AS Zip
, so.billtoname AS Buyer_Name
, qbclass.name AS Class
, CAST(soitem.datescheduledfulfillment as date) AS Fulfillment_Date
From SO
JOIN stateconst
ON so.shiptostateid=stateconst.id
JOIN qbclass
ON so.qbclassid=qbclass.id
JOIN soitem
ON so.id=soitem.soid
WHERE CAST(soitem.datescheduledfulfillment as date) = '2016-05-10'

Answer 2

您确实需要查询输出中的日期吗？因为遗漏它会解决你的问题＆＃39;：

Select DISTINCT
 so.num AS Ref
,  so.shiptoname AS Recipient_Full_Name
, so.shiptoaddress AS Address_1
, so.shiptocity AS City
, stateconst.name AS State
, so.shiptozip AS Zip
, so.billtoname AS Buyer_Name
, qbclass.name AS Class

From SO
JOIN stateconst
ON so.shiptostateid=stateconst.id
JOIN qbclass
ON so.qbclassid=qbclass.id
JOIN soitem
ON so.id=soitem.soid
WHERE DATESCHEDULEDFULFILLMENT LIKE '2016-05-10%'

SQL DISTINCT / GROUP BY无法正常工作

2 个答案: