Toolbelt.EntityFrameworkCore.IndexAttribute 1.0.1-beta

IndexAttribute for EntityFramework Core

What's this?

Revival of [Index] attribute for EF Core. (with extension for model building.)

Attention

EF Core team said:

"We didn't bring this (= IndexAttribute) over from EF6.x because it had a lot of issues"
(https://github.com/aspnet/EntityFrameworkCore/issues/4050)

Therefore, you should consider well before use this package.

How to use?

1. Annotate your model with [Index] attribute that lives in Toolbelt.ComponentModel.DataAnnotations.Schema namespace.

using Toolbelt.ComponentModel.DataAnnotations.Schema;

public class Person
{
    public int Id { get; set; }

    [Index] // <- Here!
    public string Name { get; set; }
}

2. [Important] Override OnModelCreating() method of your DbContext class, and call BuildIndexesFromAnnotations() extension method which lives in Toolbelt.ComponentModel.DataAnnotations namespace.

using Microsoft.EntityFrameworkCore;
using Toolbelt.ComponentModel.DataAnnotations;

public class MyDbContext : DbContext
{
    ...
    // Override "OnModelCreating", ...
    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);

        // .. and invoke "BuildIndexesFromAnnotations"!
        modelBuilder.BuildIndexesFromAnnotations();
    }
}

That's all!

BuildIndexesFromAnnotations() extension method scans the DbContext with .NET Reflection technology, and detects [Index] attributes, then build models related to indexing.

After doing that, the database which created by EF Core, contains indexes that are specified by [Index] attributes.

For More Detail...

This library is designed to have the same syntax as EF 6.x [Index] annotation.

Please visit document site of EF 6.x and [Index] attribute for EF 6.x.

• MSDN Document - Entity Framework Code First Data Annotations
• MSDN Document - IndexAttribute class

Not Supported Feature

IsClustered property is not supported at this version.

License

MIT License