Migrations With Referential Integrity
Posted by Max Dunn Tue, 15 May 2007 18:11:00 GMT
Migrations don’t come with referential integrity directives, best as I can tell. There are some plugins but it appeared to me (ok, after only a brief review) that they were more focused on adding referential integrity for rails object hierarchies (:belongs_to etc.), so that seemed both overkill and insufficient for what I needed to do.
But it turns out that an “execute” statement in the migration lets you issue sql directives directly.
create_table "dvectors", :id => false, :force => true do |t|
t.column "length", :integer, :default => -1
t.column "fvector", :binary
t.column "document_id", :integer, :default => -1
t.column "total_size", :integer, :default => 0
end
add_index "dvectors", ["document_id"], :name => "document_id"
execute "alter table dvectors add constraint `dvectors_fk` " +
"foreign key (`document_id`) references `documents` (`id`) on delete cascade"(Submitted by Wido Menhardt)