使用LINQ处理大型数据集

Question

每次我使用LINQ to SQL编写下面表单的程序时,我最终会得到一个程序,它在运行时会抓取越来越多的内存,并且在可能只有25,000条记录之后会消耗掉2GB的堆.我总是最终使用ADO.NET重写它.我究竟做错了什么？

澄清:这个问题与加工速度无关; 关于让它变得更快的答案是无关紧要的.

foreach (int i=0; i<some_big_number; i++)
{
    using (myDC dc = new myDC())  // my DataContext
    {
        myRecord record = (from r in dc.myTable where r.Code == i select r).Single();

        // do some LINQ queries using various tables from the data context
        // and the fields from this 'record'.  i carefully avoid referencing
        // any other data context than 'dc' in here because I want any cached
        // records to get disposed of when 'dc' gets disposed at the end of 
        // each iteration.

        record.someField = newValueJustCalculatedAbove;
        dc.SubmitChanges();
    }
}

Answer 1

您正在对数据上下文施加压力,以便每次都从头开始生成查询.

请尝试使用已编译的查询.