基于多列，大量空值将临时表附加到主表

Question

将行从会计系统带入临时表。想要将临时表中的新记录附加到主表。没有主键，因为除了查看每一列之外，行中没有唯一标识符。很多空值，因为不是每一列都需要填写。

示例数据：

分期：

    预算行|日期|资金|金额|描述|采购订单号

    1 |20140623 |xyz |12.00 |甜甜圈 |{null}
    1 |{null} |xyz |3.00 |{null} |12345
    1 |20140623 |abc |4.00 |轮胎 |{null}
    2 |20140623 |xyz |12.00 |甜甜圈 |{null}
    1 |20140623 |xyz |12.00 |鲍勃甜甜圈 |{null}

主要：

    预算行|日期|资金|金额|描述|采购订单号

    1 |20140623 |xyz |12.00 |甜甜圈 |{null}
    1 |{null} |xyz |3.00 |{null} |12345
    1 |20140623 |abc |4.00 |轮胎 |{null}

我一直是这样的：

INSERT INTO Main SELECT budget_line ,date ,fund ,amount ,description ,PO_number FROM Staging WHERE NOT EXISTS ( SELECT budget_line ,date ,fund ,amount ,description ,PO_number FROM Main WHERE ((Staging.budget_line = Main.budget_line) OR (Staging.budget_line is null AND Main.budget_line is null)) AND ((Staging.date = Main.date) OR (Staging.date is null AND Main.date is null)) AND ((Staging.fund = Main.fund) OR (Staging.fund is null AND Main.fund is null)) AND ((Staging.amount = Main.amount) OR (Staging.amount is null AND Main.amount is null)) AND ((Staging.description = Main.description) OR (Staging.description is null AND Main.description is null)) AND ((Staging.PO_number = Main.PO_number) OR (Staging.PO_number is null AND Main.PO_number is null)) )

我得到了一些没有过来的东西，我不知道为什么。我有大约 28 个字段。有没有更简单的方法来做到这一点？

Answer 1

你的 null 处理有问题..

试试这个 - 它将所有字段连接到一个键列中，并测试：

INSERT INTO Main
SELECT budget_line
,date
,fund
,amount
,description
,PO_number
FROM Staging
WHERE NOT EXISTS (
   SELECT 1
   FROM Main
   WHERE Staging.budget_line & Staging.date & Staging.fund & Staging.amount & Staging.description & Staging.PO_number =
   Main.budget_line & Main.date & Main.fund & Main.amount & Main.description & Main.PO_number)