Add indicies to labels

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

db/migrate/20140730111702_add_index_to_labels.rb

+class AddIndexToLabels < ActiveRecord::Migration
+  def change
+    add_index "labels", :project_id
+    add_index "label_links", :label_id
+    add_index "label_links", [:target_id, :target_type]
+  end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20140729152420) do
+ActiveRecord::Schema.define(version: 20140730111702) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -117,6 +117,9 @@ ActiveRecord::Schema.define(version: 20140729152420) do
     t.datetime "updated_at"
   end
 
+  add_index "label_links", ["label_id"], name: "index_label_links_on_label_id", using: :btree
+  add_index "label_links", ["target_id", "target_type"], name: "index_label_links_on_target_id_and_target_type", using: :btree
+
   create_table "labels", force: true do |t|
     t.string   "title"
     t.string   "color"
@@ -125,6 +128,8 @@ ActiveRecord::Schema.define(version: 20140729152420) do
     t.datetime "updated_at"
   end
 
+  add_index "labels", ["project_id"], name: "index_labels_on_project_id", using: :btree
+
   create_table "merge_request_diffs", force: true do |t|
     t.string   "state"
     t.text     "st_commits"