From 40181bfcab73b37e6b32fbaf8758aaeaa5157e2b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kamil=20Trzci=C5=84ski?= <ayufan@ayufan.eu>
Date: Wed, 5 Sep 2018 21:05:08 +0200
Subject: [PATCH] Fix concurrent index problem

---
 ...08_add_identifier_to_prometheus_metric.1.rb} |  1 -
 ...index_for_identifier_to_prometheus_metric.rb | 17 +++++++++++++++++
 ... => 20180831164910_import_common_metrics.rb} |  0
 db/schema.rb                                    |  2 +-
 4 files changed, 18 insertions(+), 2 deletions(-)
 rename db/migrate/{20180831164908_add_identifier_to_prometheus_metric.rb => 20180831164908_add_identifier_to_prometheus_metric.1.rb} (79%)
 create mode 100644 db/migrate/20180831164909_add_index_for_identifier_to_prometheus_metric.rb
 rename db/migrate/{20180831164909_import_common_metrics.rb => 20180831164910_import_common_metrics.rb} (100%)

diff --git a/db/migrate/20180831164908_add_identifier_to_prometheus_metric.rb b/db/migrate/20180831164908_add_identifier_to_prometheus_metric.1.rb
similarity index 79%
rename from db/migrate/20180831164908_add_identifier_to_prometheus_metric.rb
rename to db/migrate/20180831164908_add_identifier_to_prometheus_metric.1.rb
index 129e4a6e7f5..67de990757e 100644
--- a/db/migrate/20180831164908_add_identifier_to_prometheus_metric.rb
+++ b/db/migrate/20180831164908_add_identifier_to_prometheus_metric.1.rb
@@ -7,6 +7,5 @@ class AddIdentifierToPrometheusMetric < ActiveRecord::Migration
 
   def change
     add_column :prometheus_metrics, :identifier, :string
-    add_index :prometheus_metrics, :identifier, unique: true
   end
 end
diff --git a/db/migrate/20180831164909_add_index_for_identifier_to_prometheus_metric.rb b/db/migrate/20180831164909_add_index_for_identifier_to_prometheus_metric.rb
new file mode 100644
index 00000000000..f41a869199a
--- /dev/null
+++ b/db/migrate/20180831164909_add_index_for_identifier_to_prometheus_metric.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+class AddIdentifierToPrometheusMetric < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :prometheus_metrics, :identifier, unique: true
+  end
+
+  def down
+    remove_concurrent_index :prometheus_metrics, :identifier, unique: true
+  end
+end
diff --git a/db/migrate/20180831164909_import_common_metrics.rb b/db/migrate/20180831164910_import_common_metrics.rb
similarity index 100%
rename from db/migrate/20180831164909_import_common_metrics.rb
rename to db/migrate/20180831164910_import_common_metrics.rb
diff --git a/db/schema.rb b/db/schema.rb
index 5fa471a917f..333b40b34ce 100644
--- a/db/schema.rb
+++ b/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: 20180831164909) do
+ActiveRecord::Schema.define(version: 20180831164910) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"