adds project mirror data table

db/migrate/20170509153720_create_project_mirror_data.rb

+class CreateProjectMirrorData < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    execute <<-SQL
+      CREATE TABLE project_mirror_data
+      AS (
+        SELECT id AS project_id,
+          0 AS retry_count,
+          CAST(NULL AS #{timestamp}) AS last_update_started_at,
+          CAST(NULL AS #{timestamp}) AS last_update_scheduled_at,
+          NOW() AS next_execution_timestamp,
+          NOW() AS created_at,
+          NOW() AS updated_at
+        FROM projects
+        WHERE mirror IS TRUE
+      );
+    SQL
+
+    add_column :project_mirror_data, :id, :primary_key
+    change_column_default :project_mirror_data, :retry_count, 0
+    change_column_null :project_mirror_data, :retry_count, false
+    add_concurrent_foreign_key :project_mirror_data, :projects, column: :project_id
+    add_concurrent_index :project_mirror_data, [:project_id], unique: true
+  end
+
+  def down
+    drop_table :project_mirror_data if table_exists?(:project_mirror_data)
+  end
+
+  def timestamp
+    return 'TIMESTAMP' if Gitlab::Database.postgresql?
+
+    'DATETIME'
+  end
+end

db/schema.rb

@@ -1079,6 +1079,18 @@ ActiveRecord::Schema.define(version: 20170602003304) do
 
   add_index "project_import_data", ["project_id"], name: "index_project_import_data_on_project_id", using: :btree
 
+  create_table "project_mirror_data", force: :cascade do |t|
+    t.integer "project_id"
+    t.integer "retry_count", default: 0, null: false
+    t.datetime "last_update_started_at"
+    t.datetime "last_update_scheduled_at"
+    t.datetime "next_execution_timestamp"
+    t.datetime "created_at"
+    t.datetime "updated_at"
+  end
+
+  add_index "project_mirror_data", ["project_id"], name: "index_project_mirror_data_on_project_id", unique: true, using: :btree
+
   create_table "project_statistics", force: :cascade do |t|
     t.integer "project_id", null: false
     t.integer "namespace_id", null: false
@@ -1673,6 +1685,7 @@ ActiveRecord::Schema.define(version: 20170602003304) do
   add_foreign_key "personal_access_tokens", "users"
   add_foreign_key "project_authorizations", "projects", on_delete: :cascade
   add_foreign_key "project_authorizations", "users", on_delete: :cascade
+  add_foreign_key "project_mirror_data", "projects", name: "fk_d1aad367d7", on_delete: :cascade
   add_foreign_key "project_statistics", "projects", on_delete: :cascade
   add_foreign_key "protected_branch_merge_access_levels", "namespaces", column: "group_id"
   add_foreign_key "protected_branch_merge_access_levels", "protected_branches"