Model configuration: Ability to override IS NOT NULL clauses of an index

[tugberkugurlu]

This is for SQL Server and I am using EF Core 1.0.1.

Assume that I have the below entity:

public class Person
{
    public string Name { get; set; }
    public string Lastname { get; set; }
    public DateTime? DeletedOn { get; set; }
}

Inside OnModelCreating, I also have this to create a multi-column unique index:

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.Entity<Person>().HasIndex(x => new { x.Name, x.Lastname, x.DeletedOn }).IsUnique();
}

This causes EF Core to generate something similar to below:

CREATE UNIQUE NONCLUSTERED INDEX [IX_People_Name_Lastname_DeletedOn] ON [dbo].[People]
(
    [Name] ASC,
    [Lastname] ASC,
    [DeletedOn] ASC
)
WHERE ([Name] IS NOT NULL AND [Lastname] IS NOT NULL AND [DeletedOn] IS NOT NULL)

However, I want not to allow DeletedOn column to be null for this index. So, I am try to make EF Core to generate the below index creation script for me:

CREATE UNIQUE NONCLUSTERED INDEX [IX_People_Name_Lastname_DeletedOn] ON [dbo].[People]
(
    [Name] ASC,
    [Lastname] ASC,
    [DeletedOn] ASC
)
WHERE ([Name] IS NOT NULL AND [Lastname] IS NOT NULL)

QUESTION: Is this possible to do this with EF Core fluent API?

I dug a bit into the fluent API and was able to find some things related to HasAnnotation API but was not able to understand enough to achieve this.

[rowanmiller]

This is not possible. Assigning to 1.2 to look at providing this functionality.

[AndriySvyryd]

Fixed in 428a328

[Davilink]

1. Is it possible to have some example how to use it ? The documentation on https://docs.microsoft.com/en-us/ef/core/modeling/indexes doesn't explain that part.

2. Is it possible that this can be back port to EF Core 1.0.5 ? Because i have that exact same issue, but i can't use EF Core 2.0, because i need to migrate my project to dotnet Core 2.0, and for the current moment is impossible. We have so much breaking change with the new mechanism of the Identity implementation.

[ajcvickers]

@Davilink I filed dotnet/EntityFramework.Docs#610 for the docs. We will not be porting this fix to the 1.x versions of EF Core--the bar is very high to get patch changes into those releases, and this issue does not meet that bar.

[Davilink]

@ajcvickers Thx for the quick response.