When i use the query **var NewMatchs = (from x in entity.matches select x).LastOrDefault();** I got error like this **LINQ to Entities does not recognize the method 'SocialSports.Models.match LastOrDefault[match](System.Linq.IQueryable`1[SocialSports.Models.match])' method, and this method cannot be translated into a store expression.**
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I have a GridView and on a row being deleted I trigger the GridView1_RowDeleting sub, but I receive an error "LINQ to Entities does not recognize the method 'System.Web.UI.WebControls.TableCell get_Item(Int32)' method, and this method cannot be translated into a store expression." Code is:
Private Sub GridView1_RowDeleting(sender As Object, e As System.Web.UI.WebControls.GridViewDeleteEventArgs) Handles GridView1.RowDeleting
' The deletion of the individual row is automatically handled by the GridView.
Dim dbDelete As New pbu_housingEntities
' Remove individual from the bed.
Dim remove_bed = From p In dbDelete.Beds _
Where p.occupant = GridView1.Rows(e.RowIndex).Cells(3).Text _
Where p.room = GridView1.Rows(e.RowIndex).Cells(6).Text _
Where p.building = GridView1.Rows(e.RowIndex).Cells(5).Text _
Order By p.id Descending _
Select p
remove_bed.First.occupant = ""
dbDelete.SaveChanges()
' Increase number of open spaces in room.
Dim update_occupancy = From p In dbDelete.Rooms _
Where p.room1 = GridView1.Rows(e.RowIndex).Cells(6).Text
Where p.building = GridView1.Rows(e.RowIndex).Cells(5).Text _
Select p
update_occupancy.First.current_occupancy = update_occupancy.First.current_occupancy - 1
dbDelete.SaveChanges()
End Sub
The specific line erroring out is: remove_bed.First.occupant = ""
Im my MVC 3.0 Application, I created a helper like below;
[Code]....
And I used that helper in a linq query as below;
[Code]....
When I fire my app, it gives me the below error. LINQ to Entities does not recognize the method 'System.String GenerateURl(System.String)' method, and this method cannot be translated into a store expression. 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: System.NotSupportedException: LINQ to Entities does not recognize the method 'System.String GenerateURl(System.String)' method, and this method cannot be translated into a store expression. Source Error:
Line 43: public Blogs GetBlog(string urlstring) {
Line 44:
Line 45: return GetAll().SingleOrDefault(x => BlogUrlGeneration.GenerateURl(x.ArticleTitle).Equals(urlstring));
Line 46: }
Line 47:
Ä°n my blog, the link will be like below; [URL] so I need to set the above urlgenerator class into lambada. How can I do that? What would it take to make that work perfectly
I am using Entity Framework to contact my data base. as part of my web code I am using Linq to entities, and I want to determine the number of elements in an anonymous type list. I can't get it to work, I get the exception: "LINQ to Entities does not recognize the method 'Int32 Parse(System.String)' method, and this method cannot be translated into a store expression."
var questItem = from chapters in context.TestChapter
from questions in context.Question
where chapters.ID == int.Parse(Request.QueryString["id"])
where questions.TestChapterID == chapters.ID
select questions.ID;
int numOfSteps = questItem.Count();
how can I get it to work?
I am creating an Asp.net web site which will support dynamic data. When I am creating a dynamic web site from Scratch (from template in VS) all is working fine. But when I am trying to add dynamic entity (.edmx) file and running the application I am getting following error
"The method 'Skip' is only supported for sorted input in LINQ to Entities. The method 'OrderBy' must be called before the method 'Skip'. "
I have a query that gives me the average number of days between 2 dates in the database. It gives an error saying line does not reconize the subtract method. What is the best way to do this, i prefere not to have to get the whole table as a list and loop though.
Using em As EE.EclipseEntities = New EE.EclipseEntities
Return em.OrderLines.Where(Function(w) w.Received_Factory_On.HasValue) _
.Average(Function(a) CDate(a.Received_Factory_On).Subtract(CDate(a.Sent_Factory_On)).Days)
End Using
I receive this error message: LINQ to Entities does not recognize the method 'System.Guid GetUserId()' method, and this method cannot be translated into a store expression. This is my code:
DB.Users user = db.Users.FirstOrDefault(u => u.Id == BOL.GetUserId());
BOL.GetUserId() returns a GUID of the current logged-in user (and this works works).
How can I make this LINQ code line work? Or, what is the shortest alternative? In the mean time I found out that there is a difference between LINQ to SQL and Entities. I use Entities because of the TailspinSpyworks example... but my code is using LINQ to SQL. My current solution is to use a var:
var userId = BOL.GetUserId();
DB.Users user = db.Users.FirstOrDefault(u => u.Id == userId);
Is this a good solution? And, is the execution time of Entities faster than SQL?
I am building a web application in asp.Net 4.0 and entity framework. I am trying to retrieve a list of products based on a collection of id's. I first gather all the id's in a collection and then pass it to the linq query. I am trying to get a functionality similar to the IN clause in SQL. The problem seems to be with the Contains() method in the Linq to entities query. Here is my Linq code:
[Code]....
I got the above Linq to entities method from here: [URL]
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(Using SQL Server 2008 and ASP.NET MVC2)I have a simple business table and a category table. I have a 3rd table to map business to category, a many-to-many relationship. the Map table contains a BusinessID and CategoryID. I'm lost as to how I can load the categories into my Business View Model using the entities model.Without incorporating categories, my code looks like this:
[Code]....
with Business View Model defined as:
[Code]....
but if i want to populate the Categories with the mapped categories, how would one do that?
I used the auto generated models to use my existing SQL server in a new website.in some forms I use rich text editor (CKEditor) so I added [ValidateInput(false)] to those post back actions. but that is a bad solution 'caus I have lost of other from items which needs validation. I came across a potential solution to that using [AllowHtml] which I need to add to the model properties. I tried that:
[Code]....
but that is an error "type or namespace couldn't be found.."any ideas about where the [AllowHtml] attribute should be?
How to use Stored Procedures with Linq to Entities? I prefer an example with input and output The videos on asp.net only show how to do this with Linq to SQL.
View 5 RepliesI have a simple join:
SELECT * FROM MessageAlerts AS A LEFT OUTER JOIN Contacts AS C ON A.ContactId = C.Id LEFT OUTER JOIN
Users AS U ON A.UserId = U.Id INNER JOIN Businesses AS B ON B.Id = C.BusinessId OR B.UserId = U.Id
how to do this : ON B.Id = C.BusinessId OR B.UserId = U.Id with linq in entity framework.
WHY are all the examples on this site linq to SQL? Did ms not themselves announce dropping support for l2SQL over a year ago? i really don't get it. Examples are great.. but really not helping me since i've gone ahead and listened to MS. And can someone at MS clarify what the position is for linq 2 SQL.. Is it supported? Recommended? What the hell.
View 7 RepliesI am trying to learn LINQ to entities, and am working out how to best structure my BLL layer. I have generated the entity model and have created a generic repository in my DAL that returns results as IList<T>. I initially created the BLL to also return
results as IList<T>:
public IList<DAL.Customer> SelectAll()
{ [code]...
Now I am working on the aspx page, and I can create an ObjectDataSource and configure it to use my BLL, but since I am returning IList, I can't sort since I am not using a DataView. I have seen some articles on the web for converting IList to DataView, but that seems like a lot of overhead for every query.My goal is to keep a clean separation between layers without making things overly complicated. I would like to know how others have done this, or maybe a link to a good tutorial that shows how to structure all three layers.
I have a message table that self joins to itself where Message.ID == Message.Parent. So I have 1 Message with several ChildMessages. This is set up nicely with a Navigation property.
The code is currently:
var message = from m in soe.Messages.Include("ChildMessages")
where m.ID == id
&& m.IsActive
select m;
return message.FirstOrDefault();
What I really want is to only return 1 Message (that is equal to a particular ID and isActive) with all of its Active ChildMessages and I want to do it in one call to the database.
I have a table of user ids that is huge.
I have an array of user ids that I want.
I have two tables that have a foreign user id key.
What is the best way to get this information performance wise?
Ideally in SQL the final result would be somewhat like this (null values if there is no user ID in one table but not the other):
userid table1value table2value
1 null 12
5 123 null
i have a table with a field name called 'Firstname' and another field name called 'Lastname'. I would want to have a single column in my GridView which show Fullname and then the firstname and lastname are showed here under an alias. Also, i am binding my GridView using LINQ.So is there a way to create aliaswith LINQ and to use these with GridView ? Would love to have an hint about how i can realize this task.
View 5 RepliesI use the Entity Framework and Linq to Entities with MVC 2.0. When use the DropDownListFor from Html helpers to populate a dropdown that contains an ID from a foreign object, I post the form data but I can´t set the correct relation. Using the debug, I can see the ID retrieved from dropdown at my returned foreign object ID, but I think that I not use the association correctly.
View 4 RepliesIn linqtosql you could do something like:
datacontext.CreateDatabase() to generate a database from the model in sql.
I'm wanting to do the same thing in linq to entities.
Say I have a class MyEntities which inherits from ObjectContect is there a similiar method?
have already used the latest technology in a professional manner. NETBasically I have two tables related 1 to 1:the Users table and the table ProfiloPersonale is the key to the Users table that this table are ProfiloPersonale iduser and type uniqueidentifier and diagram sql server 2008 I can clearly see the report, I also did a test to insert a record in the users table ( fictional) directly from sql server and everything works.With LINQ to Entities does not work:The entities 'LEntities.Users' part of the eport 'ProfiloPersonale'.Found 'ProfiloPersonale' related to 0.Expected 1 'ProfiloPersonale'Of course what I am doing is to first create the user and then create their profile in the db, taking the id of the registered
View 1 RepliesI have a view on my database and I am trying to add a new record using the AddTo method but it is not working. I noticed that LinqToEntities is creating the insert statement like this
Insert into (select field1, field2 from my_view) (field1, field2) values (value1, value2)
Is it possible to make LinqToEntities create the insert statement like the one below ?
Insert into my_view (field1, field2) values (value1, value2)
I am trying to update an item with entity framework but I am unable to do that;
[Code]....
it didn't give any error. it passed but when I looked at the database, nothing changed. can you provide me the right way.
All I am trying to do is query the database, then get the returned values, so that I can do some calculations. But, I don't understand how to get the values from the database row that is returned, so that I can assign it for usage.
I would like to do something where the logic goes: for the index of [1] (which is just column 1), multiply it by 2. For the index of [2] (which is just column 2), multiply it by 3.
Example below:
This does NOT work:
[Code]....
In the code bdehind && syntax does not work, any ideas?
Entities ctx3 = new Entities();
var uniqueQuote = from quot in ctx3.Quotes.Include("aspnet_Users").Include("Enquiries")
where quot.Enquiries.EnquiryId == selectedEnquiryId && [code]...
Error 2 Delegate 'System.Func' does not take '1' arguments C:LocalGarageFinderLocalGarageFinderEnquiryDetail.aspx.cs 56 33 LocalGarageFinder
