LINQ-to-SQL Retrieving Data From A Different Query!
Jun 28, 2010
I have a web application that uses LINQ-to-SQL. It has a very strange issue, where a LINQ command retrieves the data that is supposed to be returned by another, totally different query that runs in a different thread. What could be the cause of this?
Specifically, a user accesses the application from his machine, opening a certain page. At the same time, another user accesses a different page from his (different) machine. One of the queries throws an exception, while the other returns the data of the first one, which comes from a very different table!
The case is always reproducible, whenever we stress the application with these two users. I've checked but I don't see any shared variables of any kind. What else could the problem be? What should I be looking for?
i"ve build a small (verry small) test app with a UI and a domain model and i'm able to show all the data from one table but now i wanna create a query so i only get the data i want but i have no idea how to do this. i've created a domain model with a entity class, an abstract and a concrete repository (see code)
[Code]....
namespace winkelketen.domain.Abstract{ public interface IwinkelketenRepository { IQueryable<Winkelketen> Winkelketen { get; } }} namespace winkelketen.domain.Concrete{ public class SqlWinkelketenRepository : IwinkelketenRepository { private Table<Winkelketen> productsTable; public SqlWinkelketenRepository(string connectionString) { productsTable = (new DataContext(connectionString)).GetTable<Winkelketen>(); } public IQueryable<Winkelketen> Winkelketen { get { return productsTable; } } }}
and then i created a UI with a controller
[Code]....
and a view
[Code]....
could something give me some tips how to do this or how to get started?
I've build a linq query.But i want a random selection so its not always ID : 1,2,3,4,5,6 How can i randomize this var? I like to bind it to a repeater.//TagCloud:
Random rand = new Random(); var tc1 = from i in JumpTide.cms.menu.GetMenuItems(32) select new
I am trying to figure out why this service does not return any data. The service does not error out is just doesn't return any data. When I take the Linq into LinqPad the query returns exactly as I expect. So I am wondering if the problem is getting my return data into a List<string>??
[Code]....
I don't know what else to say to help. When I set a break point on the "return LoanStats" line a quick watch shows an empty results view.
currently i am working on wcf...i am adding data through textborex till here is ok. but when i am retriving it from database into grid..but the grid is getting blank...
i am using this query..--page - svc.cs
public List<AddressBook> BindData() { DataClasses1DataContext dc = new DataClasses1DataContext();[code]....
I am facing a big problem with simple linq query.. I am using EF 4.0..
I am trying to take all the records from a table using a linq query:
var result = context.tablename.select(x=>x);
This results in less rows than the normal sql query which is select * from tablename;
This table has more than 5 tables as child objects (foreign key relations: one to one and one to many etc)..
This result variable after executing that linq statement returns records with all child object values without doing a include statement.. I don't know is it a default behavior of EF 4.0 . I tried this statement in linqpad also..but there is no use... But interesting thing is if I do a join on the same table with another one table is working same is sql inner join and count is same..but I don't know why is it acting differently with that table only.. Is it doing inner joins with all child tables before returning the all records of that parent table?
So the BlogPostTags table only contains 2 fields, BlogPostID and TagID.
When i run the query above i get 3 results back. Same blogpost 3 times but with 1 tag in each. It should return 1 post with 3 tags. The problem lies in the Tags query above.
'm not sure if this is the right forum, but I couldnt find one for linq related questions.I have the following problem. I have four tables, One with users, one with projects, one with the users and the projects they are in (joinProjectTable) and on table where the users can fill in there worked hours for a certain project. These hours are filled in on a daily base. Now every month there is going to be created a report on the workedHours table so there is visible which user has entered how many hours for a certain project. On this report there is gonna be a billing for the company where for the hours are worked. This is the easy part, the hard part is the following.
companies also want to have a list of users that didn't entered any hours for that particular month for a particular project. So I have to write a linq query that would look in the joinprojecttable to see which users are joined to which projects, and than with that join it should look if that particular combination (user+project) is in anyway entered in the workedhourstable for that particular month. If not this has to be shown in the datagrid, for every user that isnt in the workedhourstable for that month. So it should be a certain NOT query, but I can't seem to figure it out.does anyone have any idea to accomplisch this in Linq2Sql? I'm using VB instead of C#.
This code works just fine for me to select * from x,y,z. However what I want to do is retrieve the values return and assign them to variables. How do I go about this?
I've got a gridview that will allow clients to edit options they've already entered on another page. The gridview has three radio buttons in it each with a value of 1,2,3. The option value in the dataset is 1,2 or 3 respectively. I would like to have the radiobutton with the corresponding value selected in the gridview so they can see what they previously chose and will then be able to edit, if they wish.
I have a web app for our golf club. When I compute handicap index for each golfer, I have to select the most recent scores and then a subset of those scores depending on how many rounds of golf the golfer has played. All the scores are entered into a single SQL Express table called "Rounds". Verbally, this is what I'm trying to do:
1) select the twenty most recent golf scores (sort on date descending, "take(20)") [if less than 20 records, then select all available];
2) for this set of records, select the 10 lowest scores (or smaller number if golfer has less than 20 rounds);
3) compute the average round differential for the subset of records, etc. to calculate handicap index (this step is working ok...)
My current VB code has this LINQ query (which is flawed -- it selects the lowest handicap differential scores of ALL records for the filtered user):
[Code]....
How do I modify this query to accomplish items 1) & 2) above? It seems this should be simple, but my experience with queries is still limited.
I 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]....
List<string> EmailId= { ....} Now I have a db table Users. I need to select all users whose email exist in the above list. In sql we could write "where emailid in ('email1', email2' ,...)"
how to do this in linq to sqlquerable<Users> existingUsers = Users.getTable().where (u=>u.emailaddress in EmailId). I want to do some thing similar
I need to figure out how to express this in linq to sql:I have one or more records that contain what is essentially a wildcard sql parameter, like '100_-___-2', which should match 100[any 1 char]-[any 1 char][any 1 char][any 1 char]-2, for example. Each login will have one or more of these 'datamasks' associated with it.I need to write a query in linq to sql that does something like:
select * from something where fieldA = 'someValue' or fieldB = 'someValue'
so far, simple, but I also need to restrict the returned records to only those that match the user's 'datamasks'. I'm not sure exactly how to translate this to linq to sql... here is what a working query *without* the datamasks part looks like:
[Code]....
I need to tack on the datamasks part... can I do it right there in the same statement? or do I need to do a foreach loop on the datamasks records and append a new && condition for each one? hmmm... just thought of that as I was writing this.. I'll try that out. But I'm posting this anyway for more input... I guess that would look something like:
