linq

Where is System.Linq in .NET 4.0?

I migrated an asp.net app to 4.0. Now I am getting an error "The type or namespace name 'IQueryable' could not be found". The reference to System.Linq is invalid and I can't find it in the reference list. Where did System.Linq go? ...

How do I properly use LINQ with MySQL?

Possible Duplicate: LINQ to MySQL - what is the best option? I've been looking this up on Google for hours, but I haven't found anything conclusive. So far, I've seen a few paid options, an option with NHibernate, but most are marked as unstable or in production. Is there a stable implementation of LINQ for MySQL? ...

Is it OK to try to use Plinq in all Linq queries?

I read that PLinq will automatically use non parallel Linq if it finds PLinq to be more expensive. So I figured then why not use PLinq for everything (when possible) and let the runtime decide which one to use. The apps will be deployed to multicore servers and I am OK to develop a little more code to deal with parallelism. What are t...

The member [class] has no supported translation to SQL

Hi, I am getting the following error: Error Message:The member 'Company.ProductCore.Core.Domain.Account.Email' has no supported translation to SQL. My method looks like this: public Account GetAccountByEmail(string email) { Account account; using (WorkbookDataContext dc = _conn.GetContext()) ...

Cast LINQ Function Result to Domain Object

Hello, I have a table valued function to perform full text search on SQL server. The result type of my full text search function in LINQ is a special autogenerated type which includes KEY and RANK in addition to my regular domain object properties. So, if my regular domain object is PERSONS (with properties FirstName, LastName etc.), ...

Rewrite SQL Fulltext Function to return Table only

I have a MS SQL Fulltext Function like this: (...) RETURNS TABLE AS RETURN SELECT * FROM fishes INNER JOIN CONTAINSTABLE(fishes, *, @keywords, @limit) AS KEY_TBL ON fishes.id = KEY_TBL.[KEY] When I use this function in LINQ, it generates a special return type which includes all fields of my "fishes" table, plus Key and Rank. How cou...

Is there a better way to write this LINQ query?

Hi Is there a better simplified way to write this query. My logic is if collection contains customer ids and countrycodes, do the query ordey by customer id ascending. If there are no contain id in CustIDs then do the order by customer name. Is there a better way to write this query? I'm not really familiar with complex lambdas. var ...

LINQ aggregate / SUM grouping problem

I'm having trouble getting my head around converting a traditional SQL aggregate query into a LINQ one. The basic data dump works like so: Dim result = (From i As Models.InvoiceDetail In Data.InvoiceDetails.GetAll Join ih As Models.InvoiceHeader In Data.InvoiceHeaders.GetAll On i.InvoiceHeaderID Equals ih.ID Join p As Mo...

How to create Query syntax for multiple DataTable for implementing IN operator of Sql Server

I have fetched 3-4 tables by executing my stored procedure. Now they resides on my dataset. I have to maintain this dataset for multiple forms and I am not doing any DML operation on this dataset. Now this dataset contains 4 tables out of which i have to fetch some records to display data. Data stored in tables are in form of one to m...

LINQ to SQL: Issue with concurrency

I’m working on a sandwich ordering app in ASP.NET MVC, C# and LINQ to SQL. The app revolves around the user creating multiple custom-made sandwiches from a selection of ingredients. When it comes to confirming the order I need to know that there’s enough portions of each ingredient to fulfil all the sandwiches in the user’s order before...

LINQ into SortedList

I'm a complete LINQ newbie, so I don't know if my LINQ is incorrect for what I need to do or if my expectations of performance are too high. I've got a SortedList of objects, keyed by int; SortedList as opposed to SortedDictionary because I'll be populating the collection with pre-sorted data. My task is to find either the exact key or...

How to delete multiple records in enitity framework without looping using LINQ?

Hi I want to delete multiple records in enitity framework without using a for loop or any other loop using LINQ. Something that we can do it in SQL is there any way to delete multiple records in enitity framework ...

problem with SQL CE and orderby linq clause

Hi, I am using linq with SQL CE, but for a simple query like this: var points=from i in this.DomainBoundaryPoints orderby i.Index select i; I get this error: Could not find an implementation of the query pattern for source type 'System.Data.Linq.EntitySet<DAL.DomainBoundaryPoint>'. 'OrderBy' not found. Are you missing a reference ...

switch linq syntax

var folders = from r in this.bdd.Rights join f in this.bdd.Folders on r.RightFolderId equals f.FolderId join rs in this.bdd.RightSpecs on r.RightSpecId equals rs.SpecIdRight where r.RightUserId == userId where rs.SpecRead == true where rs.SpecWrite == true ...

find users that are following other users

Hi I'm wondering how I can go about this problem I have a DB with a Users Table, and a Followers table. The Followers table contains 2 Columns "FollowerID" and "FollowedID" I have a 1 -> * relation in my datamodel between Users.ID -> Followers.FollowerID and Users.ID -> FollowedID How do I in LINQ get a set of users that are following ...

Chain LINQ IQueryable, and end with Stored Procedure

I'm chaining search criteria in my application through IQueryable extension methods, e.g.: public static IQueryable<Fish> AtAge (this IQueryable<Fish> fish, Int32 age) { return fish.Where(f => f.Age == age); } However, I also have a full text search stored procedure: CREATE PROCEDURE [dbo].[Fishes_FullTextSearch] @searchtext nva...

How can I create a dynamic LINQ query in C# with possible multiple group by clauses?

I have been a programmer for some years now but I am a newcomer to LINQ and C# so forgive me if my question sounds particularly stupid. I hope someone may be able to point me in the right direction. My task is to come up with the ability to form a dynamic multiple group by linq query within a c# script using a generic list as a source. ...

Dynamic SQL To Dynamic LINQ in VB.NET with MS SQL Server 2008

I dread asking this question, because with what I've read so far I understand im gonna have to cram a lotta new things into my head. In spite of all the similiar questions(and the wide variety of answers) I thought I'd ask as nothing I've read tailors to what I need specifically enough. I need to represent the following query using LINQ...

Query Execution Plan - When is the Where clause executed?

I have a query like this (created by LINQ): SELECT [t0].[Id], [t0].[CreationDate], [t0].[CreatorId] FROM [dbo].[DataFTS]('test', 100) AS [t0] WHERE [t0].[CreatorId] = 1 ORDER BY [t0].[RANK] DataFTS is a full-text search table valued function. The query execution plan looks like this: SELECT (0%) - Sort (23%) - Nested Loops (Inner Joi...

Linq with a long where clause

Is there a better way to do this? I tried to loop over the partsToChange collection and build up the where clause, but it ANDs them together instead of ORing them. I also don't really want to explicitly do the equality on each item in the partsToChange list. var partsToChange = new Dictionary<string, string> { {"0039", "Vendor A"}, ...