Hi, i am trying to insert the contents of a CSV file into a database table using linq2SQL. I want to be able to rollback the transaction if ANY of the inserts fail but when i try with this code i get the following error at - db.Transaction.Commit() System.InvalidOperationException was unhandled: This SqlTransaction has completed; it is...
Hi all I have got the following LINQ query, apologies for the poor variable naming. Dim bla3 = From c In crdc.SRAs _ Where c.acad_period = ReviewCredential.AcadPeriod _ And c.periodID = ReviewCredential.PeriodID _ And c.aos_code = ReviewCredential.AoSCode _ And c.aos_period = ReviewCredential...
I have a windows application and a web service. Both have a Linq to SQL mapper with Customer table on them. Same table from the same database, same everything. I tried to send winapp.Customer object to web service but the webserviceReference.MyMethod() accepts webservice.Customer object and doesn't accept winapp.Customer as parameter. Tr...
I would like to use nLog to output my LINQ to SQL generated SQL to the log file e.g. db.Log = Console.Out reports the generated SQL to the console, http://www.bryanavery.co.uk/post/2009/03/06/Viewing-the-SQL-that-is-generated-from-LINQ-to-SQL.aspx How can I get the log to log to NLOG? ...
I know how to do this in C#, but my dev team doesn't use C#... here is the answer in C#: http://stackoverflow.com/questions/470440/linq-how-to-select-only-the-records-with-the-highest-date How do I do this in VB? Essentially, if I knew how to write lambda expressions in VB, I would be set, but the materials I have found are not helpfu...
I have two tables in which I store a tree with ordered levels like this: Table: TreeData --------------- ID (int) (primary key) Data (string) Level (int) (not null) --------------------------------------------- Table: SubTree --------------- parentID (int) (foreign key #1 to TreeData.ID) childID (int) (foreign key #2to TreeData.ID) o...
We have a small affiliate program and a simple tool to view affiliate statistics. The Linq for showing the report: from e in linq0 select new { Id = e.Id, Name = e.CompanyName, EnquiryCount = (int?)e.CampaignCodes.Sum(f => f.Enquiries.Count()) ?? 0, EnquiryOrderSum = (int?)e.CampaignCodes.Sum(f => (int?)f.Enquiries.Sum...
I'm a bit confused, I have worked with Linq To SQL and gather we can query anything in the dbml or entities e.g: var query = from i in db.mytable select i; But in the Entity Framework (which supposedly Microsoft are replacing Linq To SQL with) how can we do the same thing? Is it even possible? How does it replace Linq To S...
There are a few "should I chose this or that" questions on SO and Google, as well as a lot comparing LINQ2SQL and LINQ2E. I've seen drawbacks, differences, cons, pros, limitations, etc. I cannot say I'm an expert but I'd like to know "what would you do" if you faced this scenario and why. I have to add stuff to an "old" 2.0 app that ha...
I receive a daily XML file which I use to update a database with the content. The file is always a complete file, i.e. everything is included whether it is changed or not. I am using Linq2Sql to update the database and I was debating whether to check if anything had changed in each record (most will not change) and only update those whic...
I am running the following code: if(ven.Source == null)ven.Source = new Source(); ven.name = (string) venue.Element("venueName"); Console.WriteLine("Venue Name: " + ven.name); ven.Source.companyId = 1; ven.Source.sourceReference = (string)venue.Attribute("...
I've been learning by doing with ADO.Net Data Services (Astoria) for the last couple of months, and while I like the technology the learning has been a real trial. Information that you need to use them effectively is spread over MSDN documentation, articles, blog posts, support forums and of course StackOverflow. This question is a place...
What is the easiest way to convert an IQueryable object to a dataset? ...
I have a daily xml feed which contains all records each day. These need to be processed and loaded to a database i.e. those not included in the feed for day2 which were in day1 feed should be deleted and any differences should cause an update on the database. My current approach is to update each included record with a processed date and...
How can I use Linq-To-SQL to load a DataGridView? Would the following work? DCDataContext db = new DCDataContext(); dataGridViewJobs.DataSource = db.jobs.Select(p => p.closeDate <= DateTime.Now); ...
How do I populate the List(of Customers) in vb.net. I have the CustomersDataContext and I want to populate the customers. Please help Dim _db As New CustomersDataContext Dim _cust As New Customer Dim customers As List(Of customer) = Nothing ...
Hey all, I'm trying to do a left join in linq to sql that has a date1 > date2 comparison in it but can't figure out how. Here's the SQL: select rd.RouteDispatchID, r.RouteNumber, s.ShortDescription, rd.DispatchDate, rd.CreationDate, e.FirstName, e.LastName, count(md.MachineDispatchID) NumMachines, count(mdp.Pi...
Hi. I think a lot of people have had this issue but I'm not able to fix it or understand why I'm having it. I've been tearing hair out for a couple of hours now. I'm getting the error, "Object reference not set to an instance of an object." on my datacontext.SubmitChanges() on the SECOND time this method runs (I'm looping through a ...
I just started playing with Linq to SQL the other day and was curious if I should use it in up coming projects. I know it will save me tons of developement time. I have seen many similar questions out there on the subject but I have a few more specific questions. Is there anything wrong with inheriting the classes generated in the ...
I have an association OneToMany from class A to B (A parent property, B child property). The property setter the parent property (B.A = value) has the logic to update the id field in B to keep the entity and the id in sync. That is, whenever I assign a new value to B.A, B.Aid is also automatically updated. But if I happen to remove the...