Data Access Layer using Entity Framework

OLE DB Access Data Source using ADO.NET Entity Framework

Because an EF provider must convert c# into a particular SQL syntax, EF cannot utilize OLE DB directly (OLE DB is a connection to several DBMSs with several SQL syntaxes)....Look here ...https://jetentityframeworkprovider.codeplex.com/... if you require an EF 6.1 provider for MS Access.

Using Entity Framework and Metadata to Validate Data Annotation

Change...public class PersonMetaData { [Required(ErrorMessage = "nima", AllowEmptyStrings = false)] public global::System.String ProductName { set; get; } [Range(minimum: 10, maximum: 100, ErrorMessage = "NIIMMMAA")] public global::System.Int32 ProductID { set; get; } } ...to...public class PersonMetaData { [Required(ErrorMessa...

How do you implement a business logic layer when using entity framework as data access layer?

A "disconnected" model does not lend itself well to Entity Framework. I have never been able to easily get it to operate well unless something has changed....However, you would still need to communicate the changes back to Layer 3, which may be a hassle. You could utilize AutoMapper in Layer 2 to construct ViewModels to display to Layer 1.

N-Tier Architecture with Service Layer, Business Layer, and Entity Framework

When dependencies are being created directly in the service, why are you using dependency injection?...public IEnumerable<User> GetAllUsers() { IRepository<User> userRepository = new Repository<User>(dbContext); UserBLL userBLL = new UserBLL(userRepository); return userBLL.GetAllUsers(); } ...By the way, why do you use so many layers wh...

How to map Data Access to Business Logic objects in Entity Framework

ZZZ_tmp

Get multiple data from tables Using Entity Framework data model

You are connecting c.id and x.id. You should connect x.id contact and c.id, in my opinion. (Same issue with the phone and tag)... var data = (from c in db.Contacts from e in db.Emails.Where(x => x.id_contact == c.id).DefaultIfEmpty() from p in db.Phones.Where(x => x.id_contact == c.id).DefaultIfEmpty()...

Arranging dotnet core app for 3-tiers with data access layer

You may be searching for the ...Repository... pattern, in my opinion. It serves as a layer between your company and DAL....Here is how I recently organized a solution to keep the UI from being aware of my DAL.

How to access the database in Middleware using Entity Framework 6

ZZZ_tmp

Adding "ADO.NET Entity Data Model" uses Entity Framework 6.1.3

Currently, the EF6 tools are version 6.1.3, the ...6.2.0 is the latest EF6 runtime.... (as of writing on 2018-04-23)....Where are the EF 6.2 tools for Visual Studio?...We decided that we still needed to complete some work on the tools before we could declare them “final”. However, it did not make sense to delay the release of the runtime pa...

Entity Framework override SaveChanges() on Service layer instead of Data layer (different projects)

ZZZ_tmp