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  • WPF: DataGrid Custom. ColumnDesign with my own classes

    - by user437899
    Hi, iam looking for a datagrid which contains objects from my class. class user { string name; int ID; ... } i tried AutoGenerateColumns = true. this will add columns (name, ID, ... like the properties of my class) but i want a different design. not all attributes from the object shold be shown and the columnheader shouldn't be generated from the variablenames... if i build a custom. column-design, i cant add my objects / they will not be displayed. is it possible to define my own columns according to my objects/class. i read about databindings, but i have no idea how i can bind objects/classes in WPF. (in Visual Studio i cant choose my class as datacontext)

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  • Retrieve entities with children per one sql call. ADO.NET Entity framework

    - by Andrew Florko
    Hello everybody, I have two tables: A & B B { B1: Field1, B2: Field2, ... } A { Children: List of B, A1: Field1, A2: Field2, } I want to retrieve "A" entities with related "B" entities like this: DataContext.A.Select( a = new MySubset( A1 = a.A1, Children = a.Children.Select(b = b.B1).ToList()); But EF can't translate ToList into SQL, so i have to call ToList() per each instance in query producing additional network call. How can I avoid this? Thank you in advance.

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  • Learn Fundamentals of Silverlight 4 Data Binding

    - by Eric J.
    I'm just starting to work with Silverlight (no WPF experience either) and am having a difficult time finding a source that provides a full explanation of Data Binding. There is absolutely no lack of tutorials (starting with the ones on Silverlight.net or Scott Gu's blogs), but everything I have found is "by example". Is there a resource that explains how data binding works in Silverlight, from a Fundamental/Conceptual perspective, and provides end-to-end coverage of data binding features? The desire for a more fundamental source of information is driven by a number of questions that came up this afternoon in reviewing tutorials and writing sample apps, such as: Why can't I bind the value of a slider like this?: Value="{Binding=Age, Mode=TwoWay}" where Age refers to an int property in the object data context I bind in code-behind (the Visual Studio error message is Expected '[]'. How do I use the DataContext property in VS 2010? What's a Path, Relative Source, Static Source, ...?

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  • linq to sql string property from non-null column with default

    - by Barry Fandango
    I have a LINQ to SQL class "VoucherRecord" based on a simple table. One property "Note" is a string that represents an nvarchar(255) column, which is non-nullable and has a default value of empty string (''). If I instantiate a VoucherRecord the initial value of the Note property is null. If I add it using a DataContext's InsertOnSubmit method, I get a SQL error message: Cannot insert the value NULL into column 'Note', table 'foo.bar.tblVoucher'; column does not allow nulls. INSERT fails. Why isn't the database default kicking in? What sort of query could bypass the default anyway? How do I view the generated sql for this action? Thanks for your help!

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  • Why can't I find DataTemplates in merged resource dictionaries?

    - by dthrasher
    In my MainWindow.xaml, I have the following reference to a ResourceDictionary: <Window.Resources> <ResourceDictionary> <ResourceDictionary.MergedDictionaries> <ResourceDictionary Source="MainSkin.xaml" /> </ResourceDictionary.MergedDictionaries> </ResourceDictionary> </Window.Resources> In MainSkin.xaml, I define a datatemplate: <DataTemplate x:Key="TagTemplate"> ... </DataTemplate> Deeper within my application, I attempt to use this data template: <ContentControl DataContext="{Binding Tag}" ContentTemplate="{StaticResource TagTemplate}"/> The code compiles successfully, but when I attempt to load a Page or UserControl that contains this StaticResource, I get an exception saying that the TagTemplate can't be found. What am I doing wrong?

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  • WPF - How do I style a row based on a binding property value?

    - by Nick
    Hey! So I am trying to bind a collection of objects (IList<) to a WPF datagrid. I would like to make the row background a different color if the 'artist' property is null or empty. I am checking the value stored at the property on the LoadingRow datagrid event. Currently my implementation seems to style all of the rows with an empty or null 'artist' property correctly. The problem is that is also styles the rows where the property is not null or empty in some cases. So some rows are given the red background even though the rows 'artist' property is not null. Can anyone tell me why this could be?? Here is the LoadingRow event: private void trackGrid_LoadingRow(object sender, DataGridRowEventArgs e) { Track t = e.Row.DataContext as Track; if (String.IsNullOrEmpty(t.Artist)) { e.Row.Background = new System.Windows.Media.SolidColorBrush(System.Windows.Media.Color.FromArgb(255, 255, 125, 125)); } }

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  • Is there a .NET BCL class to help with hand-rolled property path binding?

    - by Wayne
    WPF and Silverlight have a data binding model whereby I can provide a Binding with a Path which comprises a dot-notation of property accessors down from a DataContext to a specific value inside a complex object graph (eg. MyDataContext.RootProperty.SubProperty.Thing.Value) I have a (non-UI) requirement to accept such a path expressed as a simple string, and to use reflection on an object which is (hopefully) of a type which exposes the right property getters and setters in order to read and/or write values to those properties. Before I go off and start writing the parser and reflection code, is there a handy Framework 3.5 BCL class to help with this?

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  • WPF DataGrid adding extra "ghost" row

    - by hs2d
    Hei, In my application i'm using DataGrid to show some data. To get everything working with threading i'm using AsyncObservableCollection as DataContext of DataGrid. When my application starts it looks for files in some folders and updates AsyncObservableCollection. Now here's where things go bad, when i start the application for some reason i get 2 rows with same data in DataGrid even if there is one item in collection. If i add a delay(Thread.Sleep() 50ms minimum) before executing loading files method then DataGrid show everything correctly (no extra row). Have anybody encountered something similar or is there something else i should try? Thanks in advance!

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  • Getting value of "System.Windows.Controls.TextBlock" when binding to Silverlight ComboBox

    - by sipwiz
    I'm attempting to use a Silverlight ComboBox with a static list of elements in a very simple binding scenario. The problem is the selected item is not returning me the Text of the TextBlock within the ComboBox and is instead returning "System.Windows.Controls.TextBlock". My XAML is: <ComboBox SelectedValue="{Binding Country, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnExceptions=True}"> <TextBlock FontSize="11" Text="Afghanistan" /> <TextBlock FontSize="11" Text="Albania" /> <TextBlock FontSize="11" Text="Algeria" /> </ComboBox> In my C# file I'm binding to the ComboBox using: Customer customer = new Customer() { Country = "Albania" }; DataContext = customer; The binding does not result in Albania as the selected country and updating the ComboBox choice results in the Country being set to "System.Windows.Controls.TextBlock". I've tried fiddling around with DisplayMemberPath and SelectedValuePath but haven't found the answer. I suspect it's something really simple I'm missing.

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  • Use LINQ to SQL results inside SQL Server stored procedure

    - by ifwdev
    Note: I'm not trying to call a SQL Server stored proc using a L2SQL datacontext. I use LINQPad for some fairly complex "reporting" that takes L2SQL output saved to an Array and is processed further. For example, it's usually much easier to do multiple levels of grouping with LINQ to Objects instead of trying to optimize a T-SQL query to run in a reasonable amount of time. What would be the easiest way to take the end result of one of these "applications" and use that in a SQL Server 2008 stored proc? The idea is to use the data for a Reporting Services Report, rather than copying and pasting into Excel (manual labor). The reports need to be accessible on the report server (not using the Report Server control in an application). I could output CSV and read that somehow via command line exec, but that seems like a hack. Thanks for your help.

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  • WPF: How to bind RadioButtons to an enum?

    - by Sam
    I've got an enum like this: public enum MyLovelyEnum { FirstSelection, TheOtherSelection, YetAnotherOne }; I got a property in my DataContext: public MyLovelyEnum VeryLovelyEnum { get; set; } And I got three RadioButtons in my WPF client. <RadioButton Margin="3">First Selection</RadioButton> <RadioButton Margin="3">The Other Selection</RadioButton> <RadioButton Margin="3">Yet Another one</RadioButton> Now how do I bind the RadioButtons to the property for proper two-way-binding?

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  • Style Data in a gridview which dynamically generates the columns

    - by Coesy
    I have built a dynamic gridview using the following code grdVariants.Columns.Clear(); int i = 0; foreach (DataColumn column in options.Columns) { grdVariants.Columns.Add(new GridViewColumn { Header = column.ColumnName, DisplayMemberBinding = new Binding(string.Format("[{0}]", i++)) }); } This will dynamically generate my columns at runtime, I then bind the data using lstVariantsGrid.DataContext = options; lstVariantsGrid.Items.Refresh(); This all works great and shows the data in the correct columns etc, the only issue i have is that I can't style the rows like I would in xaml as it is all an unknown quantity until runtime. Can anyone offer some advice on how I might go about doing this? One of the biggest problems I have is that one of the columns needs to display the image rather than just the path which it currently shows, as well as fiddling with fonts and colors etc. Thanks for your time.

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  • Compiled query using list of class objects in C#

    - by Sukan
    Hello , Can somebody help me out in creating compiled queries where input is to be a list of class objects? I have seen examples where Func<DataContext, somematchobject, IQueryable<T>> is created and compiled. But can I do something like Func<List<T>, matchObject, T>, and compile it? Basically I want an object(T) meeting certain conditions (as in matchObject) to be returned from a list of objects(List<T>). Will CompiledQuery.Compile help me in this? Please help me experts!!

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  • Linq to SQL Strange SQL Translation

    - by Master Morality
    I have a simple query that is generating some odd SQL translations, which is blowing up my code when the object is saturated. from x in DataContext.MyEntities select new { IsTypeCDA = x.EntityType == "CDA" //x.EntityType is a string and EntityType.CDA is a const string... } I would expect this query should translate to: SELECT (CASE WHEN [t0].[EntityType] = @p1 THEN 1 ELSE 0 END) as [IsTypeCDA] ... Instead I get this : SELECT (CASE WHEN @p1 = [t0].[EntityType] THEN 1 WHEN NOT (@p1 = [t0].[EntityType]) THEN 0 ELSE NULL END) AS [IsTypeCDA] ... Since I'm saturating a POCO where IsTypeCDA is a bool, it blows up stating I can't assign null to bool. Any thoughts? Edit: fixed the property names so they make sense...

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  • How to bind to current riacontext user in xaml

    - by Jakob
    Hi. I Have a datacontext that has a "getuserbyguid" method, i want to pass in the current logged in user.userid as a parameter, but I don't know how to bind to the current logged in user through xaml. I've tried {Binding Path=User.UserId} but without any luck. I'm using the built in riaservices authentication methods, so the userinfo should be exposed in the riacontext, or am I wrong about this? I have this for instance <riaControls:DomainDataSource x:Name="FollowingGridData" AutoLoad="True" QueryName="GetUsersFollowedByIDQuery" LoadSize="20"> <riaControls:DomainDataSource.DomainContext> <my:NotesDomainContext /> </riaControls:DomainDataSource.DomainContext> <riaControls:DomainDataSource.QueryParameters> <riaControls:Parameter ParameterName="userguid" Value="{Binding Path=User.UserId}" /> </riaControls:DomainDataSource.QueryParameters> </riaControls:DomainDataSource> But it gives me an error saying that it's not a guid, meaning that it must not be binding correctly

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  • Updating Many-to-Many relationship with LinqToSQL

    - by Noffie
    If I had, for example, a Many-to-Many mapping table called "RolesToUsers" between a Users and an Roles table, here is how I do it: // DataContext is db, usr is a User entity // newUserRolesMappings is a collection with the desired new mappings, probably // derived by looking at selections in a checkbox list of Roles on a User Edit page db.RolesToUsers.DeleteAllOnSubmit(usr.RolesToUsers); usr.RolesToUsers.Clear(); usr.RolesToUsers.AddRange(newUserRolesMappings); I used the SQL profiler once, and this seems to generate very intelligent SQL - it will only drop the rows which are no longer in the mapping relationship, and only add rows which did not already exist in the relationship. It doesn't blindly do a complete clearing and re-construction of the relationship, as I thought it would. The internet is surprisingly quiet on the subject, and the query "LinqToSQL many-to-many" mostly just turns up articles about how the LinqToSQL data mapper doesn't "support" it very well. How does everyone else update many-to-many with LinqToSQL?

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  • How to format TimeSpan in xaml

    - by biju
    I am trying to format a textblock which is bound to a TimeSpan property.It works if the property is of type DateTime but it fails if it is a TimeSpan .I can get it done using a converter.But i am trying to find out if there is any alternatives. Sample Code public TimeSpan MyTime { get; set; } public Window2() { InitializeComponent(); MyTime = DateTime.Now.TimeOfDay; DataContext = this; } Xaml <TextBlock Text="{Binding MyTime,StringFormat=HH:mm}"/> I am expecting the textblock to show only hours and mintes.But it is showing like 19:10:46.8048860

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  • Dynamic query to immediate execute?

    - by Curtis White
    I am using the MSDN Dynamic linq to sql package. It allows using strings for queries. But, the returned type is an IQueryable and not an IQueryable<T>. I do not have the ToList() method. How can I this immediate execute without manually enumerating over the IQueryable? My goal is to databind to the Selecting event on a linqtosql datasource and that throws a datacontext disposed exception. I can set the query as the Datasource on a gridview though. Any help greatly appreciated! Thanks. The dynamic linq to sql is the one from the samples that comes with visual studio.

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  • Unable to bind with any property of UserControl

    - by Agha Khan
    I looked your answer where I was also using this.DataContext=this. I am unable to convince myself why I have to remove it? But I did In my UserControl control I have 6 int properties (RedCount, GreenCount …) I am using .NET 3.5 and basically I wanted to use StringFormat with Binding. In my xaml file I have 6 Labels with I would like to bind, and I did what exactly you told in last reply. For some strange reasons it didn’t work. I don't know why it does not work. I placed break point in converter where I never hit it. This imples Binding failed.

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  • Why does this binding doesn't work through XAML but does by code ?

    - by user361899
    I am trying to bind to a static property on a static class, this property contains settings that are deserialized from a file. It never works with the following XAML : <Window.Resources> <ObjectDataProvider x:Key="wrapper" ObjectType="{x:Type Application:Wrapper}"/> </Window.Resources> <ScrollViewer x:Name="scrollViewer" ScrollViewer.VerticalScrollBarVisibility="Auto"DataContext="{Binding Source={StaticResource wrapper}, UpdateSourceTrigger=PropertyChanged}"> <ComboBox x:Name="comboboxThemes" SelectedIndex="0" SelectionChanged="ComboBoxThemesSelectionChanged" Grid.Column="1" Grid.Row="8" Margin="4,3" ItemsSource="{Binding Settings.Themes, Mode=OneWay}" SelectedValue="{Binding Settings.LastTheme, Mode=TwoWay}" /> It does work by code however : comboboxThemes.ItemsSource = Settings.Themes; Any idea ? Thank you :-)

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  • Losing scope for DataContex using LINQToSQL intermediately

    - by greektreat
    I am having a weird Situation with my DataConext. All My code is in C# I have a DLL project for my data access layer and business Layer which and Winforms project for my UI layer. My Data access Layer's Namespace is xxx.Data this is where have my xxx.dbml I also have xxx.Data.BusinessObjects name space of course for my business object in that project In my UI Layer I have these namespaces xxxApp(for Forms), xxxApp.Controls (For Controls) I have lost scope of the DataContext, it was accessible now when I do a Rebuild Solution I sometimes get compile errors saying for example: Error 34 'xxx.Data.xxxDataContext' does not contain a definition for 'SubmitChanges' and no extension method 'SubmitChanges' accepting a first argument of type 'xxx.Data.xxxDataContext' could be found (are you missing a using directive or an assembly reference?) Also intelisense doesn't recognize the methods and table classes from my xxxDataContext anymore I can access all object fine when I am in the DLL project but now in the Winforms project this is very strange. If anyone can help me out I would be extremely grateful!

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  • Silverlight Bind to TextBlock from RIA Services

    - by DaRKoN_
    I've a TextBlock that looks like so: <TextBlock Text="{Binding Name}" /> This is inside a <Canvas> with the DataContext set to MyClient which is in the ViewModel: public Client MyClient { get; private set; } // This is a RIA Entity, hence supports INotifyPropertyChanged public ViewModel() { MyClient = new Client(); LoadOperation<Client> loadClient = RiaContext.Load<Client>(RiaContext.GetClientsQuery()); loadClient.Completed += new EventHandler(loadClient_Completed); } void loadClient_Completed(object sender, EventArgs e) { MyClient = DB.Clients.Single(); } Setting MyClient like the above does not raise the PropertyChanged event. As such the UI is never updated.

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  • WPF - Weird results with DataGrid - extra line for editing entries

    - by Jim Beam
    Working with WPF and C#. I have a page with a datagrid that lists a series of objects with List as the DataContext. I recently had it working in the code behind and the Datagrid would show the extra line at the bottom of the datagrid for new entries. Now, I have moved the exact same code to its own library project. The data still appears but the extra line for entry does not and users cannot add a new record. I have already tried using grid.CanUserAddNew = true; but that does not solve it. So, it must be something in the List object - it's the exact same code as before, only pulling from a library. Help.

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  • Storing object into cache using Linq classes and velocity

    - by Arun
    I careated couple of linq classes & marked the datacontext as unidirectional. Out of four classes; one is main class while other three are having the one to many relationship with first one; When I load the object of main class & put into the memory OR serialize it into an XML file; I never get the child class data while it is maked as DataContractAttribute. How can I force object to put the child class data into XML file or into cache ?

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  • Which workaround to use for the following SQL deadlock?

    - by Marko
    I found a SQL deadlock scenario in my application during concurrency. I belive that the two statements that cause the deadlock are (note - I'm using LINQ2SQL and DataContext.ExecuteCommand(), that's where this.studioId.ToString() comes into play): exec sp_executesql N'INSERT INTO HQ.dbo.SynchronizingRows ([StudioId], [UpdatedRowId]) SELECT @p0, [t0].[Id] FROM [dbo].[UpdatedRows] AS [t0] WHERE NOT (EXISTS( SELECT NULL AS [EMPTY] FROM [dbo].[ReceivedUpdatedRows] AS [t1] WHERE ([t1].[StudioId] = @p0) AND ([t1].[UpdatedRowId] = [t0].[Id]) ))',N'@p0 uniqueidentifier',@p0='" + this.studioId.ToString() + "'; and exec sp_executesql N'INSERT INTO HQ.dbo.ReceivedUpdatedRows ([UpdatedRowId], [StudioId], [ReceiveDateTime]) SELECT [t0].[UpdatedRowId], @p0, GETDATE() FROM [dbo].[SynchronizingRows] AS [t0] WHERE ([t0].[StudioId] = @p0)',N'@p0 uniqueidentifier',@p0='" + this.studioId.ToString() + "'; The basic logic of my (client-server) application is this: Every time someone inserts or updates a row on the server side, I also insert a row into the table UpdatedRows, specifying the RowId of the modified row. When a client tries to synchronize data, it first copies all of the rows in the UpdatedRows table, that don't contain a reference row for the specific client in the table ReceivedUpdatedRows, to the table SynchronizingRows (the first statement taking part in the deadlock). Afterwards, during the synchronization I look for modified rows via lookup of the SynchronizingRows table. This step is required, otherwise if someone inserts new rows or modifies rows on the server side during synchronization I will miss them and won't get them during the next synchronization (explanation scenario to long to write here...). Once synchronization is complete, I insert rows to the ReceivedUpdatedRows table specifying that this client has received the UpdatedRows contained in the SynchronizingRows table (the second statement taking part in the deadlock). Finally I delete all rows from the SynchronizingRows table that belong to the current client. The way I see it, the deadlock is occuring on tables SynchronizingRows (abbreviation SR) and ReceivedUpdatedRows (abbreviation RUR) during steps 2 and 3 (one client is in step 2 and is inserting into SR and selecting from RUR; while another client is in step 3 inserting into RUR and selecting from SR). I googled a bit about SQL deadlocks and came to a conclusion that I have three options. Inorder to make a decision I need more input about each option/workaround: Workaround 1: The first advice given on the web about SQL deadlocks - restructure tables/queries so that deadlocks don't happen in the first place. Only problem with this is that with my IQ I don't see a way to do the synchronization logic any differently. If someone wishes to dwelve deeper into my current synchronization logic, how and why it is set up the way it is, I'll post a link for the explanation. Perhaps, with the help of someone smarter than me, it's possible to create a logic that is deadlock free. Workaround 2: The second most common advice seems to be the use of WITH(NOLOCK) hint. The problem with this is that NOLOCK might miss or duplicate some rows. Duplication is not a problem, but missing rows is catastrophic! Another option is the WITH(READPAST) hint. On the face of it, this seems to be a perfect solution. I really don't care about rows that other clients are inserting/modifying, because each row belongs only to a specific client, so I may very well skip locked rows. But the MSDN documentaion makes me a bit worried - "When READPAST is specified, both row-level and page-level locks are skipped". As I said, row-level locks would not be a problem, but page-level locks may very well be, since a page might contain rows that belong to multiple clients (including the current one). While there are lots of blog posts specifically mentioning that NOLOCK might miss rows, there seems to be none about READPAST (never) missing rows. This makes me skeptical and nervous to implement it, since there is no easy way to test it (implementing would be a piece of cake, just pop WITH(READPAST) into both statements SELECT clause and job done). Can someone confirm whether the READPAST hint can miss rows? Workaround 3: The final option is to use ALLOW_SNAPSHOT_ISOLATION and READ_COMMITED_SNAPSHOT. This would seem to be the only option to work 100% - at least I can't find any information that would contradict with it. But it is a little bit trickier to setup (I don't care much about the performance hit), because I'm using LINQ. Off the top of my head I probably need to manually open a SQL connection and pass it to the LINQ2SQL DataContext, etc... I haven't looked into the specifics very deeply. Mostly I would prefer option 2 if somone could only reassure me that READPAST will never miss rows concerning the current client (as I said before, each client has and only ever deals with it's own set of rows). Otherwise I'll likely have to implement option 3, since option 1 is probably impossible... I'll post the table definitions for the three tables as well, just in case: CREATE TABLE [dbo].[UpdatedRows]( [Id] [uniqueidentifier] NOT NULL ROWGUIDCOL DEFAULT NEWSEQUENTIALID() PRIMARY KEY CLUSTERED, [RowId] [uniqueidentifier] NOT NULL, [UpdateDateTime] [datetime] NOT NULL, ) ON [PRIMARY] GO CREATE NONCLUSTERED INDEX IX_RowId ON dbo.UpdatedRows ([RowId] ASC) WITH (STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] GO CREATE TABLE [dbo].[ReceivedUpdatedRows]( [Id] [uniqueidentifier] NOT NULL ROWGUIDCOL DEFAULT NEWSEQUENTIALID() PRIMARY KEY NONCLUSTERED, [UpdatedRowId] [uniqueidentifier] NOT NULL REFERENCES [dbo].[UpdatedRows] ([Id]), [StudioId] [uniqueidentifier] NOT NULL REFERENCES, [ReceiveDateTime] [datetime] NOT NULL, ) ON [PRIMARY] GO CREATE CLUSTERED INDEX IX_Studios ON dbo.ReceivedUpdatedRows ([StudioId] ASC) WITH (STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] GO CREATE TABLE [dbo].[SynchronizingRows]( [StudioId] [uniqueidentifier] NOT NULL [UpdatedRowId] [uniqueidentifier] NOT NULL REFERENCES [dbo].[UpdatedRows] ([Id]) PRIMARY KEY CLUSTERED ([StudioId], [UpdatedRowId]) ) ON [PRIMARY] GO PS! Studio = Client. PS2! I just noticed that the index definitions have ALLOW_PAGE_LOCK=ON. If I would turn it off, would that make any difference to READPAST? Are there any negative downsides for turning it off?

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