In EntityFramework 2.1 Fluent API Setting Audit Fields on Insert

Question

Using Entity Framework's Fluent API, I can successfully insert a new row in the user's table using this code:

 modelBuilder.Entity<User>().ToTable("Users");
 modelBuilder.Entity<User>().HasKey(x => x.UserId);

However, I also want to set the CreatedBy field based on the Guid assigned to the UserId. The following code does not work:

 modelBuilder.Entity<User>().Property(x => x.CreatedBy)
      .HasDefaultValueSql("SCOPE_IDENTITY()");

I would appreciate any suggestions. Thanks.

Answer 1

This can be done using the .HasComputedColumnSql.

Example:

modelBuilder.Entity<Contact>()
            .Propery(p => p.LastModified)
            .HasComputedColumnSql("GetUtcDate()");


protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.Entity<SalesOrderHeader>()
    .Property(e => e.SalesOrderNumber)
    .HasComputedColumnSql("isnull(N'SO'+CONVERT([nvarchar](23),[SalesOrderID]),N'*** ERROR ***')");
}

Here is the link you can refer to:

HasComputedColumnSql Method

hope this helps,

HK