实体框架绩效不佳

Question

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Am using EF 6.1.1 in C# Windows Forms Application and facing strange issues on Performance factor.

My database has a table with name Ticket and has 49300 records. This table has multiple other tables linked. Entity Framework diagram is available at: http://i.imgur.com/u4gKVFI.png

The record counts are as follows:

BillableOption  4  
Company 390  
Contact 687  
Location    3  
Member  16  
ServiceBoard    6  
ServiceItem 0  
ServicePriority 8  
ServiceSource   5  
ServiceStatus   93  
ServiceSubType  668  
ServiceType 20  
Ticket  49300  
TimeEntry   52518  
TimeEntryMember 0  
WorkRole    10  
WorkType    5

My EF Data Context is globally available as a static variable of a class. When I fire following code, it takes 12-15 seconds to load data (only talking about .ToList() method). and bind with DataGridView. Is there any way to increase the performance?

public static List LoadTicket()
    {
        bool lastValue1 = DataAccessLocal.dc.Configuration.AutoDetectChangesEnabled;
        bool lastValue2 = DataAccessLocal.dc.Configuration.ProxyCreationEnabled;
        DataAccessLocal.dc.Configuration.AutoDetectChangesEnabled = false;
        DataAccessLocal.dc.Configuration.ProxyCreationEnabled = false;
        var returnValue = (from r in DataAccessLocal.dc.Tickets.AsNoTracking()
                           select new LinqTicket
                           {
                               Summary = r.Summary,
                               DetailDescription = r.Summary,
                               Resolution = r.Resolution,
                               CompanyName = r.Company.CompanyName,
                               ContactName = (r.Contact == null ? string.Empty : r.Contact.FirstName + " " + r.Contact.LastName),
                               BoardName = r.ServiceBoard.ServiceBoardName,
                               Priority = r.ServicePriority.ServicePriorityName,
                               Source = r.ServiceSource.ServiceSourceName,
                               Location = r.Location.LocationName,
                               ServiceType = r.ServiceTypeRecId == null ? string.Empty : r.ServiceType.ServiceTypeName,
                               ServiceSubType = r.ServiceSubTypeRecId == null ? string.Empty : r.ServiceSubType.ServiceSubTypeName,
                               ServiceItem = r.ServiceItemRecId == null ? string.Empty : r.ServiceItem.ServiceItemText,
                               StatusName = r.ServiceStatus.ServiceStatusName,
                               TicketRecId = r.TicketRecId,
                               RemoteTicketId = r.RemoteTicketRecId.Value,
                               DueDate = r.RequiredDate == null ? new DateTime(1900, 1, 1) : r.RequiredDate.Value,
                               EstimatedHours = r.BudgetHours == null ? 0 : r.BudgetHours.Value,
                               ServiceBoardId = r.ServiceBoard.ServiceBoardRecId,
                               InternalStatus = r.InternalStatus.HasValue == true ? (enmInternalStatus)r.InternalStatus.Value : enmInternalStatus.OK,
                               LastUpdatedByMemberRecId = r.LastUpdatedByMemberRecId
                           }).ToList();

        DataAccessLocal.dc.Configuration.AutoDetectChangesEnabled = lastValue1;
        DataAccessLocal.dc.Configuration.ProxyCreationEnabled = lastValue2;
        return returnValue;
    }

Answer 1

If you really need to bind that many records to the DataGridView, you should use Virtual Mode .

Quote from msdn Implementing Virtual Mode with Just-In-Time Data Loading in the Windows Forms DataGridView Control :

One reason to implement virtual mode in the DataGridView control is to retrieve data only as it is needed. This is called just-in-time data loading .