Error trying to show a result in a gridview

[Nigel]

Hi, I am just starting with OpenAccess and thought the first thing to try would be to output some information into a gridview. But I am getting the following error:

Any operation that will fully resolve the query may not be called once a 'get' operation was performed

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: Telerik.OpenAccess.Exceptions.InvalidOperationException: Any operation that will fully resolve the query may not be called once a 'get' operation was performed

Source Error:

Line 76: Line 77: RadGrid1.DataSource = result; Line 78: RadGrid1.DataBind(); Line 79: } Line 80:

Source File: C:\Project Files\IC-Solutions\IC-Solutions\IC-Solutions\Default.aspx.cs    Line: 78

Stack Trace:

[InvalidOperationException: Any operation that will fully resolve the query may not be called once a 'get' operation was performed] Telerik.OpenAccess.SPI.Backends.ThrowException(Exception e) +28 Telerik.OpenAccess.RT.ExceptionWrapper.Throw() +34 OpenAccessRuntime.DataObjects.ForwardQueryResult.resolve() +117 OpenAccessRuntime.DataObjects.ForwardQueryResult.get_Count() +107 Telerik.OpenAccess.RT.ListEnumerator.get_Count() +42 Telerik.Web.UI.GridDataTableFromEnumerable.FillData() +2136 Telerik.Web.UI.GridResolveEnumerable.Initialize() +55 Telerik.Web.UI.GridResolveEnumerable.EnsureInitialized() +40 Telerik.Web.UI.GridResolveEnumerable.get_DataTable() +31 Telerik.Web.UI.GridEnumerableFromDataView..ctor(GridTableView owner, IEnumerable enumerable, Boolean CaseSensitive, Boolean autoGenerateColumns, GridColumnCollection presentColumns, String[] additionalField, Boolean retrieveAllFields) +222 Telerik.Web.UI.GridDataSourceHelper.CreateGridEnumerable(GridTableView owner, IEnumerable enumerable, Boolean caseSensitive, Boolean autoGenerateColumns, GridColumnCollection presentColumns, String[] additionalField, Boolean retrieveAllFields) +155 Telerik.Web.UI.GridDataSourceHelper.GetResolvedDataSource(GridTableView owner, Object dataSource, String dataMember, Boolean caseSensitive, Boolean autoGenerateColumns, GridColumnCollection presentColumns, String[] additionalField, Boolean retrieveAllFields) +556 Telerik.Web.UI.GridTableView.get_ResolvedDataSource() +219 Telerik.Web.UI.GridTableView.CreateChildControls(IEnumerable dataSource, Boolean useDataSource) +73 System.Web.UI.WebControls.CompositeDataBoundControl.PerformDataBinding(IEnumerable data) +57 System.Web.UI.WebControls.DataBoundControl.OnDataSourceViewSelectCallback(IEnumerable data) +114 System.Web.UI.DataSourceView.Select(DataSourceSelectArguments arguments, DataSourceViewSelectCallback callback) +31 System.Web.UI.WebControls.DataBoundControl.PerformSelect() +142 Telerik.Web.UI.GridTableView.PerformSelect() +28 System.Web.UI.WebControls.BaseDataBoundControl.DataBind() +73 Telerik.Web.UI.GridTableView.DataBind() +365 Telerik.Web.UI.RadGrid.DataBind() +165 IC_Solutions._Default.Button2_Click(Object sender, EventArgs e) in C:\Project Files\IC-Solutions\IC-Solutions\IC-Solutions\Default.aspx.cs:78 System.Web.UI.WebControls.Button.OnClick(EventArgs e) +111 System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +110 System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10 System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13 System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1565

The page looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using SiteDataObjects;
using Telerik.OpenAccess;

namespace IC_Solutions
{
    public partial class _Default : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {

        }

        protected void RadGrid1_NeedDataSource(object source, Telerik.Web.UI.GridNeedDataSourceEventArgs e)
        {
            /*IObjectScope scope = ObjectScopeProvider1.ObjectScope();
            scope.Transaction.Begin();
            IQueryResult result = scope.GetOqlQuery("Select * from ProductExtent AS x").Execute();
            RadGrid1.DataSource = result;
            scope.Transaction.Rollback();*/
        }

        protected void Button2_Click(object sender, EventArgs e)
        {
            IObjectScope scope = ObjectScopeProvider1.ObjectScope();
            IQueryResult result = scope.GetOqlQuery("Select * from ProductExtent AS x where x.ProductTitle Like $1").Execute("*" + TextBox1.Text +"*" );

            RadGrid1.DataSource = result;
        }


    }
}

And a Product looks like this:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Telerik.OpenAccess;

namespace SiteDataObjects
{
    [Persistent]
    public class Product
    {
        public long productID;
        public string ProductTitle;
        public string ProductShortDescription;
        public string ProductDetails;

        public ManufacturerManufacturer;
        public Category Category;

        public IList<SupplierProduct> SupplierItems = new List<SupplierProduct>();

        public TaxCode Tax;

        public IList<Product> RelatedProducts = new List<Product>();

   }

Any ideas?

Thanks in advanced

[Dimitar Kapitanov]

Hello Nigel,
The queries are optimized for sequential reads by default. Please set the IQuery.ForwardOnly property to False, to allow non-sequential operations (probably what the grid does internally) and the error should disappear.
Hope that helps.

Greetings,
Dimitar Kapitanov
the Telerik team

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[Nigel]

That got it, thanks heaps

[Awais]

Can You Please tell me, Where i can set this Property (Iquery.ForwardOnly) to FALSE...

[Jan Blessenohl]

Hello Awais,
There are three ways to do it, it is dependent on the query api you are using:

            // 1.
            IQuery q = scope.GetOqlQuery("select * from PersonExtent");
            q.ForwardsOnly = false;
            IQueryResult r = q.Execute();

            // 2.
            var r = from p in scope.Extent<Person>() select p;
            r.ForwardsOnly = false;

            //3.
            scope.GetOqlQuery<Person>().ExecuteList();

Kind regards,
Jan Blessenohl
the Telerik team

Instantly find answers to your questions on the new Telerik Support Portal.
Check out the tips for optimizing your support resource searches.