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.

Haithem KAROUI · Accepted Answer · 2018-10-18 08:58:44Z

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

answered Oct 18, 2018 at 8:58

Haithem KAROUI

1,6114 gold badges22 silver badges40 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

IMOsiris Over a year ago

First, thanks for the response. Users can be created by themselves or by others. When a user creates his own account, I want to set CreatedBy to UserId. However, when someone else creates the account, I want to set CreatedBy to the passed in Id. Thus, CreatedBy must accept an Id or use a default. HasComputedColumnSql will not accept a passed in value. Alternatively, I was hoping that HasDefaultValueSql could reference a column within the record (like UserId) for its value, but it cannot. Do you have any additional thoughts?

Haithem KAROUI Over a year ago

i think that if you have some business rules behind you better not do that inside the model builder, intead, do it when creating entities by using static heper method with sets the created by filed of the new entity by a value based on your business condition...

Collectives™ on Stack Overflow

In EntityFramework 2.1 Fluent API Setting Audit Fields on Insert

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related