Question

以下列方式的数据表;

Firm | PartID | StockCount |       Date | Type
-----------------------------------------------------------
   1 |     71 |          5 | 2014-02-01 | Incoming Invoice
   1 |     71 |         -1 | 2014-02-09 | Send Invoice
   1 |     71 |         10 | 2014-02-13 | Stocktaking  ( !!! Of the Depot. )
   1 |     71 |         -1 | 2014-02-21 | Send Invoice
   1 |     71 |          5 | 2014-02-28 | Incoming Invoice

这张表实际上是一张股票，是一张虚构的动作表描写。此表中的商店，购买和销售发票中的计数包括。这样，从仓库和仓库进入仓库将收集在实际计算的表数量中。从进行人口普查的那一刻起，股票价值应该按照规定的金额计算。问题即将来临。

如何获得以下结果？

Firm | PartID | StockCount |       Date | Type
-------------------------------------------------------
   1 |     71 |         14 |       NULL | NULL

Answer 1

如果我正确阅读：

SELECT firm, partid, count(stockCount) as stock_total
FROM yourtable
WHERE firm = 1
AND partid = 71

如果要选择多个部分，则需要分组，例如：

SELECT firm, partid, count(stockCount) as stock_total
FROM yourtable
WHERE firm = 1
GROUP BY partid

Answer 2

试试这个

SELECT Firm,
       PartID,
       Count(StockCount),
       Date AS NULL,
       TYPE AS NULL
FROM TABLE
GROUP BY Firm,
         PartID

Answer 3

您对此问题的解释尚不清楚，但我认为这是您想要的。

SELECT Firm, PartID, SUM(StockCount) as StockCount, NULL as Date, NULL as Type
FROM tbl T1
WHERE Date >= (SELECT Date FROM tbl T2
                  WHERE T2.Type = Stocktaking
                   AND T1.Firm =T2.Firm
                   AND T1.PartId = T2.PartId
              )
GROUP BY Firm, PartID

Answer 4

你似乎想要＆＃34;库存＆＃34;之后的股票总和，我怀疑它通常被称为＆＃34;做库存＆＃34;用英语。

select Firm, PartId, sum(StockCount) as StockCount, NULL as Date, NULL as Type
from table t
where Date >= (select max(Date)
               from table t2
               where t2.Firm = t.Firm and
                     t2.partid = t.partid and
                     t2.type = 'Stocktaking'
              )
group by Firm, Partid;

如果可能没有Stocktaking记录，那么请采用left join方法：

select Firm, PartId, sum(StockCount) as StockCount, NULL as Date, NULL as Type
from table t left join
     (select Firm, PartId, max(Date) as maxDate
      from table t
      where t2.type = 'Stocktaking'
      group by Firm, PartId
     ) as tfp
     on t.Firm = tfp.Firm and t.PartId = tfp.PartId and t.Date >= tfp.MaxDate
group by t.Firm, t.PartId;

MySQL如何在盘点后计算

4 个答案: