如何在数据表中获取"件"列的总和？

Question

如何在数据表中获取"件"列的总和？说我有下表.如何计算article ="milk"和artno ="15"的"总"件数？

Columns:   article     artno    pieces
Rows:
1          milk        15       1
2          water       12       1
3          apple       13       2
4          milk        15       1
5          milk        16       1
6          bread       11       2
7          milk        16       4

我的新DataTable的结果应该是这样的:

Columns:   article     artno    pieces
Rows:
1          bread       11       2
2          water       12       1
3          apple       13       2
4          milk        15       2
5          milk        16       5

我的代码:

foreach (DataRow foundDataRow in foundRows1)
{
    int i = 0;
    foreach (DataRow dataRow in foundRows2)
    {
        if (object.Equals(dataRow.ItemArray[0], foundDataRow.ItemArray[0])
            && object.Equals(dataRow.ItemArray[3], foundDataRow.ItemArray[3]))
        {
            i = i + Convert.ToInt16(dataRow.ItemArray[4]);
        }
    }
    Debug.Print(i.ToString());
}

对不起,但我是新的DataBase开发人员,我的英语口语不太好.

Answer 1

使用该DataTable.Compute方法,您可以:

int sum = (int)table.Compute("Sum(pieces)", "article = 'milk' AND artno='15'");