Add nested groups support on data level

* add parent_id field to namespaces table to store relation with nested groups
* create routes table to keep information about full path of every group and project
* project/group lookup by full path from routes table

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/db/migrate/20161202152035_add_index_to_routes.rb b/db/migrate/20161202152035_add_index_to_routes.rb
new file mode 100644
index 00000000000..4a51337bda6
--- /dev/null
+++ b/db/migrate/20161202152035_add_index_to_routes.rb
@@ -0,0 +1,16 @@
+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class AddIndexToRoutes < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  # Set this constant to true if this migration requires downtime.
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def change
+    add_concurrent_index(:routes, :path, unique: true)
+    add_concurrent_index(:routes, [:source_type, :source_id], unique: true)
+  end
+end