从TXT和分组中获取数据并减去

Question

尝试从txt文件中获取数据，该文件包含以下格式的买卖。我想按项目分组并互相减去。

我进行了三个查询，例如totalin，totalout和库存，但是当我从in中减去时，缺少了一些未售出的项目。

这是数据表

+------+---------+--------+
| TYPE |  ITEM   | AMOUNT |
+------+---------+--------+
| BUY  | APPLE   |    100 |
| BUY  | ORANGE  |    100 |
| BUY  | APPLE   |    200 |
| BUY  | ORANGE  |    200 |
| SELL | APPLE   |     50 |
| SELL | APPLE   |     50 |
| SELL | ORANGE  |    100 |
| SELL | ORANGE  |    100 |
| BUY  | COCONUT |     50 |
| SELL | BANANE  |     30 |
+------+---------+--------+

我想要此输出

+---------+--------+
|  ITEM   | AMOUNT |
+---------+--------+
| APPLE   |    200 |
| BANANE  |    -30 |
| COCONUT |     50 |
| ORANGE  |    100 |
+---------+--------+

我对想要的结果进行了3次查询，但不幸的是我被困住了。

这是我的查询

第1个查询，共：

SELECT DATA.TYPE, DATA.ITEM, Sum(DATA.AMOUNT) AS TOTALIN
    FROM DATA
    GROUP BY DATA.TYPE, DATA.ITEM
    HAVING (((DATA.TYPE)="BUY"));

查询2总计：

SELECT DATA.TYPE, DATA.ITEM, Sum(DATA.AMOUNT) AS TOTALOUT
    FROM DATA
    GROUP BY DATA.TYPE, DATA.ITEM
    HAVING (((DATA.TYPE)="SELL"));

查询3库存：

SELECT DATA.ITEM, [BUY]![TOTAL_IN]-[SELL]![TOTAL_OUT] AS STOK
FROM (DATA INNER JOIN BUY ON DATA.ITEM = BUY.ITEM) INNER JOIN SELL ON DATA.ITEM = SELL.ITEM
GROUP BY DATA.ITEM, [BUY]![TOTAL_IN]-[SELL]![TOTAL_OUT];

我如何进行查询，将其余的显示为库存。

非常感谢。

Answer 1

您可以一口气总结：

SELECT ITEM, 
       Sum(iif(data.type = "BUY", AMOUNT, -AMOUNT)) AS Stock
    FROM DATA
    GROUP BY ITEM;

Answer 2

您可以将卖出视为-ve，将买入视为+ ve金额。

然后查询变成如下

select item
       ,sum(case when type='BUY' then Amount
                 when type='SELL' then -Amount
             end) as Amount
  from data_table
 group by item

Answer 3

在MsAccess中，您可以使用iif function应用if-logic块，并按如下所示一步来运行查询。

SELECT item,   
SUM(iif ([type] = "SELL", (-1 * Amount), Amount)) as amounts   
FROM data   
GROUP BY item