Problem with the query

Question

I am using sqlserver 2000.When i run a query for the first time..it is executing in particular time like 12 sec and when i am executing the same query the next time,it is executing in more or the less time like 4 sec,14sec. If the time varies like this, my application doesn't work well. Can you give any solution for this problem?

Answer 1

HI,

 i thought about it and i would probably approach it with a MultiBinding and a respective ValueConverter, i.e.

<StackPanel>
    <StackPanel.Resources>
        <local:ComboBoxItemsSourceFilter x:Key="ComboBoxItemsSourceFilter"/>
    </StackPanel.Resources>
    <ComboBox Name="cb1">
        <ComboBox.ItemsSource>
            <MultiBinding Converter="{StaticResource ComboBoxItemsSourceFilter}">
                <Binding Path="Emps"/> <!-- Source collection binding -->
                <Binding ElementName="cb2" Path="SelectedItem"/>
                <Binding ElementName="cb3" Path="SelectedItem"/>
            </MultiBinding>
        </ComboBox.ItemsSource>
    </ComboBox>
    <ComboBox Name="cb2">
        <ComboBox.ItemsSource>
            <MultiBinding Converter="{StaticResource ComboBoxItemsSourceFilter}">
                <Binding Path="Emps"/>
                <Binding ElementName="cb1" Path="SelectedItem"/>
                <Binding ElementName="cb3" Path="SelectedItem"/>
            </MultiBinding>
        </ComboBox.ItemsSource>
    </ComboBox>
    <ComboBox Name="cb3">
        <ComboBox.ItemsSource>
            <MultiBinding Converter="{StaticResource ComboBoxItemsSourceFilter}">
                <Binding Path="Emps"/>
                <Binding ElementName="cb1" Path="SelectedItem"/>
                <Binding ElementName="cb2" Path="SelectedItem"/>
            </MultiBinding>
        </ComboBox.ItemsSource>
    </ComboBox>
</StackPanel>

public class ComboBoxItemsSourceFilter : IMultiValueConverter
{
    #region IMultiValueConverter Members

    public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
    {
        var collection = new List<object>((object[])values[0]);
        foreach (var item in values.Skip(1))
        {
            if (item != null) collection.Remove(item);
        }
        return collection;
    }

    public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
    {
        throw new NotSupportedException();
    }

    #endregion
}