Entity Framework Core - Knowledge Base (KB)

Save detached object graph using Entity Framework code first causes Primary Key violation

I'm trying to save an object graph of POCOs I have mapped to EF6 using Code First fluent notations....Upon saving the object graph however, I stumble upon primary key violation exceptions....The object graph is quite simple:...One ...Issue... can contain ...

How to get primary key value with Entity Framework Core

We are currently using the method below which depends upon IObjectContextAdapter in an abstract Repository. From what I'm reading, it appears that anything related to ObjectContext is being chopped out of Entity Framework Core. The method below is the o...

Changing Primary Key using Entity Framework Core Migrations

I am trying to Change the Primary key of a table via Entity Framework Core Migrations:...protected override void Up(MigrationBuilder migrationBuilder) { migrationBuilder.DropPrimaryKey( name: "PK_Permissions", table: "Permi...

How to use a varchar column other than Id for PK?

I have a table which has ...Code... as PK, but I get the exception below in ...DefaultEditionCreator.cs... once I try to run the application....[Table("Test")] public class Test: FullAuditedEntity<string> { [DatabaseGenerated(DatabaseGeneratedOption.I...

How to read from a table without a primary key in Entity Framework Core 2.0?

I am having a problem reading from a table in my SQL Server without a primary key. I have defined an entity class such as:...public class PerfData { public Int64 ActivityId { get; set; } public Int64 Numbers{ get; set; } } ...And the ...DbContext...

The entity type requires a primary key to be defined error with key attribute

Setting up a proof of concept app. I've added an ...ApplicationDbContext... class and my ...Transaction... class to the ...Web Application (Model-View-Controller)... template in VS2017....When I try to run ...Add-Migration AddsTransactions... I get this e...

Entity framework core - user specified primary key value not saving

I am using this code to save a student to student table. ID is the primary key in the table...._context.Add(student); await _context.SaveChangesAsync(); ...A student object with these values works and the record is added with the next available ID in the ...

.Net Core auto-generated string primary key

.Net Core 2.2 Identity framework has string primary key which is an auto-generated GUID. My question is how to have an auto-generated STRING primary key using Entity Framework 2.2?