add/drop FOREIGN KEY for existing table+column in Ecto migration

[Petrică Clement Chiriac]

Hi,

I see at http://hexdocs.pm/ecto/Ecto.Migration.html#references/2

we have a way to create FOREIGN KEY when add column.

But how to add this FOREIGN KEY/REFERENCES when

table and column already exists?

To drop and add FOREIGN KEY is util for import/export.

If no option here I can use direct DDL SQL

def up do

  execute """

   ALTER TABLE Orders ADD FOREIGN KEY (Persons_Id) REFERENCES Persons(Id)

  """

end

Thanks,

Petrica Clement Chiriac