I am trying to simply update the entity object and I get this error.. All the googling on the error I did takes me to complex explanations... can anyone put it simply? I am working of of this simple tutorial http://aspalliance.com/1919_ASPNET_40_and_the_Entity_Framework_4__Part_2_Perform_CRUD_Operations_Using_the_Entity_Framework_4.5 ...
Hi all, I've been following with great interest the converstaion here: http://stackoverflow.com/questions/3769141/construct-query-with-linq-rather-than-sql-strings with regards to constructing expression trees where even the table name is dynamic. Toward that end, I've created a Extension method, addWhere, that looks like: static pub...
I'm trying to do some really dynamic querying here - preferably without invoking the compiler at runtime though. I have a string containing a LINQ expression, e.g. var s = "from a in queryable where a.Type == 1 select a"; How can I get the resulting IQueryable or Expressions from that? I've seen LINQPad and RavenDb both do this so I...
(EDIT: I have asked the wrong question. The real problem I'm having is over at http://stackoverflow.com/questions/3782940/compose-linq-to-sql-predicates-into-a-single-predicate - but this one got some good answers so I've left it up!) Given the following search text: "keyword1 keyword2 keyword3 ... keywordN" I want to end up with t...
(An earlier question, http://stackoverflow.com/questions/3782799/recursively-compose-linq-predicates-into-a-single-predicate, is similar to this but I actually asked the wrong question... the solution there satisfied the question as posed, but isn't actually what I need. They are different, though. Honest.) Given the following search te...
I am getting a cast error with Linq to a DataTable that was populated with Oracle. bool isTrue = DataTable.AsEnumerable().Any (x => x.Field<int>("MYNUMBERFIELD") == MYNUMBER); In SQL this works fine as expected. In Oracle is fails with a cast error on the cast. In C# code the same thing happens when you do the following: i...
In LinqPad I have the following query statements... var genre = "Anime & Animation"; var minRating = 3.0; var topNum = 30; var query = (from g in Genres from t in g.Titles where g.Name==genre && t.Instant.Available==true && t.AverageRating >= minRating orderby t.AverageRating descending select new {t.Name...
How to get values from nested Dictionary using LINQ. Keys in the Dictionary are integer. Values of Dictionary are list of lists. Seconday level list is a list of array holding integer value. Thanks in advance. ...
I need to retrieve values from dictionary which stores a ArrayList which in turn has an ArrayList This second ArrayList has int array stored . Now how can I retrieve those integer values. ` Dictionary<int, ArrayList> obj = new Dictionary<int, ArrayList>(); ArrayList objList1 = new ArrayList(); ArrayList objLi...
I have List object filled with instances of a custom struct. list.Add(new Mail("mail1", "test11", "path11")); list.Add(new Mail("mail2", "test12", "path12")); list.Add(new Mail("mail1", "test13", "path13")); list.Add(new Mail("mail1", "test14", "path14")); list.Add(new Mail("mail2", "test15", "pat...
I have two List<T> of objects with different types (i.e., List<Apple> and List<Tiger>). Now I want to combine properties from the 2 objects to generate a new (anonymous) type of objects. How do I achieve with LINQ? ...
Are there any sane analogues to LINQ (.NET) exists for Scala? ...
I'm attempting to write a CompiledQuery using Linq-to-Entities that will replace a stored procedure that takes two array (in this case, comma-delimited TEXT) parameters. Essentially, the SQL is be something like this: *Stored Proc definition* @ArrayParm1 TEXT, @ArrayParm2 TEXT -- etc. SELECT [fieldList] FROM someTable WHERE som...
I'm using the Mono.CSharp library to emit code. Following another question on SO (http://stackoverflow.com/questions/3407318/mono-compiler-as-a-service-mcs) I managed to get Mono.CSharp evaluating correctly on the Microsoft CLR. To add flexibility in my app I'd like to be able to customize a query at runtime - by allowing the user to p...
Apologies - am not good at SQL. Perhaps this is a simple query - I don't know. What I have is a basic forum table - e.g. id poster title type content postedon parentID in this scheme, if a user asks a question, it is type = 0, and if it is an answer, type = 1. If the entry is an answer, I update the parentID to the id on the question...
Hi all, I'm working with a pretty nasty looking, but non-changable db. We've got a table, called "Locations" with column, "Position" This column has values like "A SHELF 5" Which means "Case A, Shelf 5". In an ideal world, I'd have a Case and Shelf column, with the values "A" and 5, respectively. What I'm wondering, is if there's a...
I have an XML in this format which is mapped to corresponding Objects in VB.NET. <Control Name="LoginPage" LabelAlignment="Right" FieldAlignment="Left" DisplayPoweredByLogo="False"> <Fields> <FieldGroup Name="Admin" Visible="True" LayoutPosition="Left"> <AdminID Visible="False" Required="False" EnableChange="False" Max...
In the database of an application I'm using, there is a record that has a "Date" field. In many places in the code, we need to translate that into a Fiscal Year for grouping, selecting, and filtering. So here are a few examples of what a query might look like: var query = from r in DB.records let fy = r.Date.Month >= 10 ? r....
Thanks in advance for any assistance. I'm not even sure if this is possible, but I'm trying to get a list of duplicate files using their hashes to identify the list of files associated with the hashes. I have this below: Dictionary<FileHash, string[]> FindDuplicateFiles(string searchFolder) { Directory.GetFiles(searchFolder, "*.*")...
Hi i have this SQL SELECT * FROM [dbo].[LeftHand] left outer JOIN [dbo].[Head] ON [LeftHand].[ID] = [Head].[LeftHand_Id] WHERE [Head].[RightHand_Id] Not IN (59,60,63,64,65) or [Head].[RightHand_Id] is null [Head] */ \* / \ 1/ \1 [LeftHand] [RightHand] ([LeftHand may h...