DATEDIFF in linq (in months)

The LINQ expression node type 'Invoke' is not supported in the entity framework's LINQ to Entities.

This problem can be solved using the AsExpandable() method present in LINQKIT by Joe Albahari. He's the same creator of ...PredicateBuilder... that I see you're using....If querying with Entity Framework, change the last line to this:...return objectContext.Products.AsExpandable().Where(predicate);...You can grab LINQKIT DLL ...here... or install i...

Entity Framework: Efficient month grouping

The reason for poor performance is that the whole table is fetched into memory (AsEnumerable()). You can group then by Year and Month like this...var trendData = (from d in ExpenseItemsViewableDirect group d by new { Year = d.Er_Approved_Date.Year, Month = d.Er_Approv...

Linq query with month difference between 2 dates

If you're under .NET 4+ you could try ...EntityFunctions.DiffMonths... utility method e.g.:...var query = query .Where(i=> EntityFunctions.DiffMonths(i.FromDate, i.ToDate) == 2 );

Entity Framework 6 SqlFunctions DateDiff not implemented in nuget package

I was looking in the wrong place. The correct function was in System.Data.Entity.SqlServer.SqlFunctions. The correct query turned out to be ...RepositoryFactory.CreateReadOnly<MyEntity>() .Where(at => at.AccessedDate.HasValue && at.CreatedDate >= startDate && at.CreatedDate <= endDate && SqlFunctions.DateDiff("ss", at.CreatedD...

Using DateDiff with Linq.Dynamic library for fetching today records

Use ...DbFunctions....Where(p => DbFunctions.DiffDays(p.AddedDate, DateTime.Now) == 0) ...Edit:...If you want to invoke this dynamically, you'll need to modify code for the Dynamic LINQ....Download the ...sample project containing DynamicLibrary.cs.... The file is located under App_Code folder....Find the static definition for ...predefinedTypes...

ASP.Net MVC - Razor Displaying account totals for customers by Month/Year Columns

Your existing code is only returning a collection of ...MonthlyTotalsVM... where a value actually exists and the key to making this work is to initialize the collection with a ...MonthlyTotalsVM... for each month in the range of dates you want to display and then update the corresponding item in the collection based on the index of the month....Ass...

Only parameterless constructors and initializers are supported in LINQ to Entities in linq join with tuples

Use the anonymous type to fetch from the database and convert to a Tuple in memory....var list = ( from a in db.CategoryRatings join c in db.OverallPerformanceByCategories on a.CategoryRatingId equals c.CategoryRatingId where c.ReviewId == review.ReviewId select(new {a.CategoryRatingName, a.CategoryWeight, c.Score}) ) .AsEnu...

Entity Framework groupby day to day in month

To make this work with EF and SQL, you can just do some date math to compute a "period" number for grouping. Basically, you convert each date to the month, offset by the 16th, plus add an offset for the year:...var result = await db.Orders.Where(o => o.OrderDate > date) .GroupBy(o => o.OrderDate.Month + 12*(o.OrderDate.Y...

Unable to cast object of type 'System.Linq.Expressions.MethodCallExpression' to type 'System.Linq.Expressions.LambdaExpression'

You can assign a variable for ..._ratingsProvider.GetRating... first, to avoid the error in the title....After that you will have another error saying entity framework does not support your query. You need something like LINQKit ...https://github.com/scottksmith95/LINQKit.... ...AsExpandable()... and ...Invoke(x, id)... are from LINQKit....using Li...

How to get first day of month/year etc?

It should be possible using ...System.Linq.Dynamic.Core.......EFCore...void Main() { var r = Reservations.Select("DateTime(CheckinDate.Year,1,1)"); r.Dump(); } ...EFCore Result...EFCore Generated SQL...EF 6...For Entity Framework 6, you need to use:...var datesDynamic = ctx.Reservations.Select("DbFunctions.CreateDateTime(CheckinDate.Year, 1...