ADO.NET问题 [英] ADO.NET problem

问题描述

大家好，
我有一个问题...我一次读取了20000行，但是我只使用了一行，经过处理后，我又使用了另一行.
我该怎么办?
请回复.

看到这里:

Hi everybody,
I have one problem... I read 20000 rows at a time, but I use only one row and after processing, I use another row.
How can I do this?
Please reply.

See here:

con = new SqlConnection(nrdet);
       SqlDataAdapter da = new SqlDataAdapter("select E1,SM1,R1,E2,SM2,R2,E3,SM3,R3,E4,SM4,R4,E5,SM5,R5,E6,SM6,R6,E7,SM7,R7,E8,SM8,R8,E9,SM9,R9,E10,SM10,R10 From TOTAL_NR WHERE SCHEME=''" + DropDownList1.SelectedItem.Text + "'' AND YR=''" + DropDownList2.SelectedItem.Text + "'' AND RESULT=3", con);
       DataSet ds = new DataSet();
       da.Fill(ds);

实际上，这里有2000行，但是我要逐行比较行.

我先使用E1，SM1，R1值，然后比较E2，SM2，R2之后的结果...

Actually, here there are 2000 rows, but I compare rows one after another.

I use E1,SM1,R1 values first I compare those results after E2,SM2,R2.....

推荐答案

您可以遍历结果集吗? br/> 我可能没有正确理解您的问题-也许您需要在此处发布一些代码.

You can loop through the result set?
I may not have understood your question properly - maybe you need to post some code here.

获取对DataTable对象的引用并遍历行集合

Get a reference to the DataTable object and loop through the rows collection

DataSet ds = new DataSet();
da.Fill(ds);

DataTable dt = ds.Tables[0];

foreach(DataRow dr in dt.Rows)
{
    // Now use the dararow object to access your column fields
    if (Convert.ToInt32(dr["YourIntegerFieldName"]) == WhateverTest)
    {
        // Do something?
    }
}

hmm，当您使用数据集时，一次获取所有记录并将其保留在内存中，而将它们保留在内存中时，您将比较行中的值，

但我想建议您使用一次仅获取一条记录的SqlDataReader，这在性能方面会很好，但是如果您要使用断开连接的数据访问，则需要在进程完成时保持db连接，或编辑记录中的数据，数据集就可以了.
但是在这种情况下，使用数据集意味着您可以在内存中保留20000条记录.

hmm when you use the dataset you take all the records at once and keep them in the memory , while keeping them in memory you compare the values in the row,

but i would like to suggest you to use the SqlDataReader which takes only one record at a time , it will be good in performance wise , but u need to keep the db connection while process completes , if you want to use a disconnected data accessing, or editing data in the record, dataset is good .
but in this case using dataset means you keep 20000 records in memory.

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