ADO.NET :: How To Properly Close Out A System.Data.Linq.DataContext Object
Apr 1, 2011
I have a System.Data.Linq.DataContext object and need to know the proper way of closing it out before it goes out of scope in order to prevent the following error when making a bunch of database changes:
Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached.
Can I just call obj.Dispose() or do I need to call obj.Connection.Dispose() or obj.Connection.Close()?
I guess what I want to know is will calling obj.Dispose() end up executing the functionality in obj.Connection.Dispose() and obj.Connection.Close(). The MSDN documentation that I found on these functions does not have this information (at least I didn't see it - I could have mistakenly overlooked it).
View 3 Replies
Similar Messages:
May 28, 2010
I have a strange problem. I am adding a LinqDatasource object, and set the context:
[Code]....
Then I get this error:The type 'System.Data.Linq.DataContext' is defined in an assembly that is not referenced. You must add a reference to assembly 'System.Data.Linq, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'.
On web.config I already have this:
<add assembly="System.Data.Linq, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"/>
NOTE: The datacontext is in a different project (DLL proect) where I added a refernce to System.Data.Linq.
is there another way adding a refernce to a web project? or only though teh web.config?
View 12 Replies
Mar 31, 2010
I wanted to delete the record from data but I receive this error "Unable to cast object of type 'System.Data.Linq.DataQuery`1[training_eval.Course]' to type 'training_eval.Course'.
Dim eval_sure = From ev In db.Evaluates Where ev.course_id = indexcourse Select ev.course_id
Dim del_course = From c In db.Courses Where c.Course_id = indexcourse
db.Courses.DeleteOnSubmit(del_course)
db.SubmitChanges()
View 4 Replies
Jan 10, 2011
I am trying to publish asp.net mvc site on remote server I am getting the error as shown in figure.
View 2 Replies
Mar 20, 2010
I'm trying to use linq to sql for my project (very short deadline), and I'm kind of in a bind. I don't know the best way to have a data context handy per request thread. I want something like a singleton class from which all my repository classes can access the current data context. However, singleton class is static and is not thread-safe and therefore not suitable for web apps. I want something that would create a data context at the beginning of the request and dispose of it along with the request
View 1 Replies
Feb 12, 2010
For no apparent reason (of course there must be one), my web project will no longer generate LINQ to SQL classes/data contexts!!!I am going about the usual routine of right clicking the project, adding new item, selected LINQ to SQL classes, then dragging over a table from Server Explorer, saving and build but no...the bloody thing won't appear!!!Does anyone know why this might be happening/what have I done wrong?
View 1 Replies
Sep 7, 2010
i am working on Linq,as we know to use any table in linq we have to drag and drop it on our datacontext's Designer File,and at run time we got its value,till here no any problem,main point is if any changes in respective data source's schema has made ,then on datacontext we will not get that changes,for it we have to change this datacontext manually by by again drag and drop,it will not happen implicitly when this changes has been made on the data source. how i solve this problem so that datacontext change implicitly without any over head using .net 3.5.
View 2 Replies
Mar 26, 2010
System.Data.Linq.ChangeConflictException: 2 of X updates failed. at System.Data.Linq.ChangeProcessor.SubmitChanges(ConflictMode failureMode) at System.Data.Linq.DataContext.SubmitChanges(ConflictMode failureMode) at PROJECT.Controllers.HomeController.ClickProc(Int32
id, String code, String n)
This is what I get very often. This action is done thousands of times a day, and I get this exception about once every 5 seconds. From what I understand it happens when something changes in the database in the period between creating DataContext and updating it. Am I right?How can I fix it?I just debugged the error and found the following:
[Code]....
The Stats table is updated constantly. So how can I still make LINQsave the changes. With "classical" MS SQL access through SqlDataCommand I never had problems like that.
View 5 Replies
Jan 21, 2010
I have a linq DataSource and a Grid in my htnl and I want to access the DataContext from code behind. Now in the past when I do evrything in code behind I just use...
DataContextName db = new DataContextName();
and I have my reference.
Now I can still do that and it works fine it just seems odd to be making a second class object when there is one that is made from the linq DataSource in the html. But I can't figure out how to get a reference to the DataContext that is created from my html code.
View 2 Replies
Mar 5, 2011
I am trying to return all records from a table using a Linq strongly typed datacontext. I want this in its own dll and accessible via a public method. I am basing this on the following MSDN example:
[URL]
I get no intellisense for appt in the Linq code and I also get a compile error for Table<Appointments>:
The type or namespace name 'Appointments' could not be found (are you missing a using directive or an assembly reference?)
Here is my code:
[Code]....
View 2 Replies
Mar 30, 2010
I'm studing Linq on TheBeerHouse Project,I would create a my Linq Version.I have a big problem with Updating, this i a part of source :
protected static ArticlesDataContext GetContext()
{
return new ArticlesDataContext(Settings.ConnectionString);
[code]...
View 2 Replies
Aug 20, 2010
I am writing an application in C# that uses LINQ to validate a datacontext off a textbox to see if the record exists already. If the record does exist I inserted an if statement to advise the user that the record exists, if the record does not exist I would like to allow the record to be added to the database. If I take out my else statement everything works fine as far as inserting goes, but I do not want to allow inserts in this scenario. I have tried moving the if and else statement to different parts of the code but can't quite figure this one out.
[Code]....
View 3 Replies
Mar 20, 2010
I need my linq to sql datacontext to be available across my business/data layer for all my repository objects to access. However since this is a web app, I want to create and destroy it per request. I'm wondering if having a singleton class that can lazily create and attach the datacontext to current HttpContext would work. My question is: would the datacontext get disposed automatically when the request ends? Below is the code for what I'm thinking. Would this accomplish my purpose: have a thread-safe datacontext instance that is lazily available and is automatically disposed when the request ends?
public class SingletonDC
{
public static NorthwindDataContext Default
{
get
{
NorthwindDataContext defaultInstance = (NorthwindDataContext)System.Web.HttpContext.Current.Items["datacontext"];
if (defaultInstance == null)
{
defaultInstance = new NorthwindDataContext();
System.Web.HttpContext.Current.Items.Add("datacontext", defaultInstance);
}
return defaultInstance;
}
}
}
View 1 Replies
Aug 13, 2010
I'm new to LINQ and have a problem with my query not showing me the Table Collection. I manually created my Cart class and specified the table attributes on each property (works fine for inserting records via LINQ see below). DataContext dc = new DataContext(Conn);
var q = (from c in dc.NOTABLES?? where ((c.UserID == userID)) orderby c.CreateDateTime Based on examples I would expect to see dc.Cart But I don't, so I tried to access it via dc.GetTable<Cart>() which at least gets me data but doesn't seem to convert the rows to my Cart object since this:
foreach (var cart in q) Log.Info("UserID: " + cart.UserID + " CartID: " + cart.ID.ToString());
blows up with a "Specified Cast is Not Valid" exception.
No Problem Inserting Also, I had no problem inserting data into the database:
DataContext dc = new DataContext(Conn);
Table<Cart> Carts = dc.GetTable<Cart>();
Cart aCart = new Cart();
aCart.UserID = userId;
aCart.Description = description;
aCart.CreateDateTime = System.DateTime.Now;
aCart.UpdateDateTime = System.DateTime.Now;
Carts.InsertOnSubmit(aCart);
Carts.Context.SubmitChanges();
View 1 Replies
Feb 10, 2011
I am trying to run a linq query but I need the result as a datatable as I am using that to store records from different queries in the same viewstate object.The 2 versions below compile, but return an empty set. The exact error is "Value cannot be null.Parameter name: source". (and yes I have checked there is data):
MyDatabaseDataContext db = new MyDatabaseDataContext(conn);
IEnumerable<DataRow> queryProjects =
(from DataRow p in db.STREAM_PROJECTs.AsEnumerable()
[code]...
View 1 Replies
Aug 20, 2010
my table column is:
AttachContent varbinary (max)
when i try to retrieve the data and i get this below error, i am using linq
cannot convert from 'System.Data.Linq.Binary' to 'System.IO.BinaryReader'
View 1 Replies
May 5, 2010
I want to create a LINQ DataContext Class as per Database Design. I getting a problem in some cases.
the syntax to bulid a LINQ class :
[Code]....
Here Table Name Is HardCoded But I my case my Table Name A Changed as Finicial Year Change.So How I Give The TableName As RunTime
View 8 Replies
Jan 5, 2010
Unable to cast object of type 'System.Web.UI.LiteralControl' to type 'System.Web.UI.WebControls.TextBox'.
[code]....
View 3 Replies
Oct 1, 2010
Basically, what I did is that: I have a table in SQL database and some of data fields allow null. I built Objectdatasource through dataset. When I built update page using dataset. It generate the following error before showing the update page correctly. It seems I have issue to retrieve the null value from the database through using objectdatasource through dataset. Any suggestions?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
View 6 Replies
Sep 30, 2010
I am trying to upload a picture into database using FormView insertItemTemplate. FormView is bounded by objectdatasource.To upload, I placed FileUpload control inside insertItemTemplate.In table the dataType is image.Error:Object of type 'System.Boolean' cannot be converted to type 'System.Byte[]'.
View 3 Replies
Jan 25, 2010
I'm integrating a number of e-comm sites into different banks and decided the easiest method was to add in the dotnetcharge (www.dotnetcharge.com) library.It works well and means I can keep much of my code the same for each bank type and transaction.However, their support is a bit sucky (4 emails sent, 1 reply) and I'm utterly baffled on the 3D Secure issue.Does anyone have experience with dotnetcharge and 3D Secure?I have set the MerchantURL and the actual 3D Secure screen comes up - but I'm unsure how to get the system to 'flow' properly.Does anyone have any code examples or even pointers in the right direction?Failing that.This particular integration is with SagePay,which also has God-awful documentation and support.
Code for reference is as follows;
[code]...
View 2 Replies
Nov 15, 2010
I've just used Visual Studio to create a linq to sql class. In the .designer.cs file the code includes:using System.Data.Linq;However, when I compile the projeget:Compiler Error Message: CS0234: The type or namespace name 'Linq' does not exist in the namespace 'System.Data' (are you missing an assembly reference?)The code is completely generated by Visual Studio
View 5 Replies
Jul 13, 2010
[Code]....
[Code]....
View 4 Replies
Jan 27, 2011
I've never actually implemented a registration/login system before, so I'm trying my hand at making my own in C#/ASP.NET (not using ASP.NET's built-in membership provider). What I'm a little unclear on is how to utilize Session/cookies to keep a user logged in during and between sessions.
protected void Login_User(object sender, EventArgs e)
{
string username = usernameField.Text;
string password = passwordField.Text;
User user = UserRepository.FindUser(username);
if (user != null)
{
if (user.Password.Equals(Hash(password)))
{
// How do I properly login the user and keep track of his session?
}
else
Response.Write("Wrong password!");
}
else
Response.Write("User does not exist!");
}
View 3 Replies
Feb 2, 2010
I wasted the better part of the day on this and am no closer to a understanding the issue than what I was this morning.
I am looping through a set of objects and marking them for deletion. The 2nd one always causes the above exception. tb_invoice has a FK to tb_shipment.
As always, I am probably missing something very obvious, but I have stripped out so much from this code already that there is nothing left, and I am still getting this exception. This is a local SQL 2008 instance and there is of course nothing and nobody changing the invoice in between reading them and calling SubmitChanges().
myDataContext db = new myDataContext();
IQueryable<invoiceDetail> pendingInvoices
db.GetInvoiceDetailPending();
foreach (invoiceDetail id in pendingInvoices) {
tb_shipment s = db.GetShipmentById((Guid)id.shipment_id);
db.tb_invoices.DeleteOnSubmit(
db.GetInvoiceById(s.tb_invoices.FirstOrDefault().id)); }
SubmitChanges(); // fails for the 2nd invoice
}
View 1 Replies
