for example,
var result = from category in myEntities.Categories
where category.UserId == userId
orderby category.CategoryName
select category;
What is the type of "result"? I casted it to an IQueryable variable and it worked except it did not have some of the methods normally available, e.g. Count(). In my program I have to cast it to some explicit types and then use the Count() method.
i have a new question: i read all the tutorials that i found but i cannot understand how to pass a result of a linq to entities result to the view so that i can display the results. My query is actually in the controller function ot the view, i would now loop the results and display them in the page. How?
View 23 RepliesI have this ListView that has a Drop Down List.Everything works fine (I think/hope) except that the drop down list are not showing its result correctly.This is the code.
Front-End
[Code]....
The code behind consist of the page_load and the ItemDataBound
[Code]....
I'm having a problem with my Linq to XML query. I'm getting the result data I want, but it's nested so deep that there must be a better way.Here is my XML:
[Code]....
I'm trying to get a list (simple string[]) of all Item IDs where Category Names contains "Other".Here is my Linq:
[Code]....
[Code]....
Here is a snapshot of my result from Visual Studio:The results I want are there ("item100", "item400", "item500"), but buried so deeply in the results var.
How can I get the query to return a simple
string[] = { "item100", "item400", "item500" }
can get two tables in only one query with LINQ to Entities
Code for example:
[Code]....
If I have a linq query that creates the anonymous type below:
select new
{
lf.id,
lf.name
lf.desc,
plf.childId
};
Is it possible to assign a specific type to one of the members? Specifically I would like to make lf.id a null-able int rather than an int...
I have an Interface that has its concrete class defined via a factory. Because of this I found no way to use the Interface tpye directly in my LINQ quesry so I had to use the concrete class types to creat a generic list. The LINQ query works but after calling.ToList() on the LINQ query result I get a List(of MyConcreteClass), but I need a List(of IMyConcreteClass). I have tried everything I can find: .Cast, Ctype, implicit casting, etc. but I always get back one of the (2) messages (depending on if I attempt to cast)message:
"Unable to cast object of type 'System.Collections.Generic.List`1[MyConcreteClass]' to type 'System.Collections.Generic.IEnumerable`1[IMyConcreteClass]'."
...or
"Unable to cast object of type '<CastIterator>d__aa`1[IMyConcreteClass]' to type 'System.Collections.Generic.List`1[MyConcreteClass]'."
Here is the sample code:
[Code]....
How can I use Order by on the result of a LinQ to SQL query ?
I have the following Situation:
Dim ret As New Object
ret = From status In tableStatus _
Select status.STATUS_ID, _
Text = Function_GetText(status.TEXT_ID)
Now I have to order this result on the field Text, has anyone an idea? (I can't use in my case Orde by Function_GetText(status.TEXT_ID))
How to randomize a LINQ query result?
Below takes 4 of the records but it won't randomize in every request. [:(]
Dim products = (From p In Northwind _
Order By Guid.NewGuid _
Select New With { _
.Name = p.Name, _
})
Return products.Take(4).ToList()
i want take a single value result from linq query
if i have :[Code]....
the variable result does not return nothing, only tostring() and similar how can i get a single result from linq query and use it in my ID variable?
New to Linq and Var type have a method where linq query is executed, want to return the result and assign it to GridView. but method don't take the return type as var.
So was wondering how do i return this query result?
Should i assign this result to DataTable first and make the method return type as DataTable?
Here is the code, This is what i want to do but not sure what is the right way
[Code]....
I am running a LINQ query which populates a list used by a DropDownList, I need to insert an "Unassigned" value to the list. The function below queries the values correctly from the db but does not insert the "Unaasinged" value to the list.
[Code]....
I am new to this, and I am trying to implement a linq query similar to db.Genres.Include("Albums") command from
mvc music store using my current DB setup. I realize that the tutorial mentions Checlking the "Include foreign key columns in the method" when creating the tables in ADO.NET, but if I am using LINQ to SQL classes, then how can I obtain the same effect. And how do I use
db.Genres.Include("Albums") to simplify my life?
How do i check if linq insert/update query was successfull or how many rows were added/updated?
View 1 RepliesI'm having trouble writing what should be a simple sub-query using LINQ to Entities. I have two tables: Customers and Orders that have a relation on the CustID field. Not all Customers have a record in the Orders table, while some have mutiple records. In traditional SQL, you could write the query like this: SELECT * FROM Orders where CustID IN (SELECT CustID FROM Customers) I know this could be done as a JOIN in both SQL and L2E, but my actual query is more complex (about 8-9 joins), so I am hoping to find a L2E sub-query equivalent. Something like this:
[Code]....
I know LINQ to Entities does not support the " IN " clause, so I am looking for something that will work in its place.
I have a few tables, Listings, ListingImages and a few others related to Listings. ListingImages is related to Listings so that you can have many ListingImages per Listing.
When I query this table I do;
[code].....
Now this is fine. However, I now want to sort the ListingImages independently within each Listing (by an ImageOrder column I have in that table).
How can I do this and pass all my Includes(...). Would it be bad form to sort the ListingImages within the View as this solution seems to work?
I am consuming an RSS feed to display on my website using a repeater control. I was wondering if it's possible in VB to return an anonymous type from my linq query rather than a collection of strongly typed RSSItems. I know this is possible in C#, however haven't been able to work out a VB equivalent.
[Code]....
I am trying to fill a gridview with the data from Product table selecting few columns . I am using 3 - tier architecture and in DAL getproduct(userid) I am writing the query but cannot figure out exactly how to get that working .. here is piece of method I wrote
public List<Project> GetProjectList(int ownerId)
For context: First of all, I am new to LINQ, as I have been using SubSonic for quite some time now.
I have two tables, Users, and Affiliates. They both have a very typical schema. The FK that joins them is the UserId field, which is in the Affiliates table. I want to create a LINQ query that pulls the Username from the Users table using the AffiliateId value. The AffiliateId is a primary key of the Affiliates table.
I have tried to accomplish this using many variations of the following code:
[Code]....
In the above query, I expect to get a single row result set. However, I instead receive the entire table of results.
How can I make this work? I have yet to see an example or article out there to do what I am trying to do.
I am working on a content management system which is being sort of retrofitted onto an existing database, and the database has many many tables. There will be a staging database, where we will make changes and allow users to 'preview in place'. Then any changes have to be approved, and to publish them we will connect to a live version of the same database (same schema) and play-forward the captured changes.I have found some code (called Doddle Audit) which, with some customization, is giving me great information about what is changing. I am able to get a list of all columns, before and after, for updates, inserts, and deletes. But what I would really like to have is the underlying SQL being run by SubmitChanges(). LinqToSql has to generate this, so why can't I have it? I have googled around and looked at code involving SubmitChanges, mousing over stuff, and I can't seem to find it. Does anyone know of a way to obtain this?
View 4 RepliesI'm looking to translate an SQL query into linq
INNER JOIN Usrs ON
SAQ.UserId =
Usrs.UserId AND Scan.UserId =
Users.UserId
I'm not sure how to include the "AND" in the LINQ statement.
I am trying to display this query result in an aspx page.
It is very slow in loading. Here is the query. The inner query inside the outer quesry is the problem.(Please see the underlined part in the query) - (If I remove that part it is very fast.)
select
top 500
--This column is the issue
,Governing_Class=( case when exists (select top 1 tqc.class_code from
t_quote_class tqc
inner join t_quote_class_premium tqcm on tqc.class_code =tqcm.
class_code
where tqc.appid=pi.appid and tqc.class_code not in('8742' ,'8810','7380')
order by tqcm.premium_amt desc
)
then ( select top 1 tqc.class_code from
t_quote_class tqc
inner join t_quote_class_premium tqcm on tqc.class_code =tqcm.
class_code
where tqc.appid=pi.
appid
order by tqcm.premium_amt desc
)
......... From tables
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 Replies