sql - 如果值小于 10 SQL，则计算上一个上次购买价格

Question

我的选择查询中有以下子查询，它根据上次购买日期获取产品的最后购买日期、购买日期、订单号和供应商。但是，我需要对其进行修改，以便如果最后一次购买少于 10 美元，它将进入下一个最后一次购买日期，依此类推，并相应地填充购买日期、订单号和供应商。

有什么建议我会怎么做？

Answer 1

添加purchamt >= 10条件应该会有所帮助

,LastPurchase=(SELECT TOP (1) purchamt AS LastPurchase 
FROM purchase AS p 
WHERE (masterid = m.masterid) 
    AND (purchvendorid <> '')
    AND purchamt >= 10
ORDER BY purchasedate DESC)

,PurchaseDate=(SELECT TOP (1) purchasedate 
FROM purchase AS p 
WHERE (masterid = m.masterid) 
    AND (purchvendorid <> '')
    AND purchamt >= 10
ORDER BY purchasedate DESC)

,PONo=(SELECT TOP 1 do.orderno 
FROM [purchase] p INNER JOIN dealorder do on do.orderid = p.purchasepoid 
WHERE (masterid = m.masterid) 
    AND (purchvendorid <> '')
    AND purchamt >= 10
ORDER BY purchasedate DESC)

,vendor=(SELECT TOP 1 v.vendor 
FROM [purchase] p INNER JOIN vendor v on v.vendorid = p.purchvendorid 
WHERE (masterid = m.masterid) 
    AND (purchvendorid <> '')
    AND purchamt >= 10
ORDER BY purchasedate DESC)

Answer 2

我不知道我是否正确理解了您的问题，但您想要的只是购买金额应大于 10，只需在您的子查询中添加即可。它将忽略金额 < 10 的所有购买日期。

希望这可以帮助。

SELECT TOP (1) purchamt AS LastPurchase 
FROM purchase AS p 

WHERE (masterid = m.masterid) 
    AND (purchvendorid <> '')
    and purchamt  > 10
ORDER BY purchasedate DESC