Can JSONB GIN indexes be specified in CodeFirst EntityFramework with NPGSQL?

Question

I've got some JSONB columns on my EF code first objects in an EFCore project. I would like to set up some GIN indexes to properties inside those strongly typed objects being stored as JSONB property/column.
Is this possible? (currently using the postgres:latest image)

Thanks.

Answer 1

Since .ForNpgsqlHasMethod("gin") is obsolete, with EF Core 3.1 you can use this:

metaBuilder
    .HasIndex(x => x.DocumentNumber)
    .HasMethod("gin")
    .HasOperators("gin_trgm_ops");

and your migration will look like this:

migrationBuilder.CreateIndex(
    name: "IX_DocumentContentMeta_DocumentNumber",
    table: "DocumentContentMeta",
    column: "DocumentNumber")
    .Annotation("Npgsql:IndexMethod", "gin")
    .Annotation("Npgsql:IndexOperators", new[] { "gin_trgm_ops" });

Answer 2

Well, actually u can do it like this

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.Entity<Artist>()
       .HasIndex(a => new { a.Album })
       .ForNpgsqlHasMethod("gin");

    base.OnModelCreating(modelBuilder);
}

and when u run ef add migration, the sql query generated will be like:

CREATE INDEX ix_artist_album ON artist USING gin ("album");

Documentation in Npgsql: http://www.npgsql.org/efcore/modeling/indexes.html