SQL 加入导致多个重复条目

Question

我在弄清楚如何摆脱第一个 table 的骗局时遇到了麻烦。请在此处查看突出显示的行以供参考 enter image description here

这是我输入的公式

SELECT
     "Classes.Class Name" AS Customer,
     "Customers.Customer Name" as docket,
     "Items.Item Name" as EST_Item,
     Quantity as EST_Qty,
     "Unit Price" as EST_UnitPrice,
     "Query_Bill Line items"."Items.Item Name" as BILL_Item,
     "Query_Bill Line items"."Quantity" as Bill_Qty,
     "Query_Bill Line items"."Unit Price" as Bill_UnitPrice
FROM  "Query_Estimate Line Items" LEFT JOIN "Query_Bill Line Items" ON "Query_Estimate Line Items"."cUSTOMERS.cUSTOMER NAME"  = "Query_Bill Line Items"."CUSTOMERS.CUSTOMER NAME"
 AND    "Query_Estimate Line Items"."iTEMS.ITEM NAME"  = "Query_Bill Line Items"."ITEMS.ITEM NAME"

抱歉列名超长！我缺少什么来摆脱表 1 中的欺骗“"Query_Estimate Line Items"?

谢谢

Answer 1

要减少行数，您需要按某些内容（例如 Customer、Docket、EST_Item）进行分组，并汇总未分组的列（例如 Bill_Qty 或 Unit_Price).你知道如何使用group by吗？

SQL 加入导致多个重复条目

SQL Join resulting in multiple duplicate entries

sql

left-join

zoho