Merge branch 'remove-temporary-ci-index' into 'master'

Remove a temporary index on ci_builds meant only for earlier migration

See merge request gitlab-org/gitlab-ce!14378

changelogs/unreleased/remove-temporary-ci-index.yml

+---
+title: Remove an index on ci_builds meant to be only temporary
+merge_request:
+author:
+type: other

db/migrate/20170919211300_remove_temporary_ci_builds_index.rb

+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class RemoveTemporaryCiBuildsIndex < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  # Set this constant to true if this migration requires downtime.
+  DOWNTIME = false
+
+  # To use create/remove index concurrently
+  disable_ddl_transaction!
+
+  def up
+    return unless index_exists?(:ci_builds, :id, name: 'index_for_ci_builds_retried_migration')
+    remove_concurrent_index(:ci_builds, :id, name: "index_for_ci_builds_retried_migration")
+  end
+
+  def down
+    # this was a temporary index for a migration that was never
+    # present previously so this probably shouldn't be here but it's
+    # easier to test the drop if we have a way to create it.
+    add_concurrent_index("ci_builds", ["id"],
+                         name: "index_for_ci_builds_retried_migration",
+                         where: "(retried IS NULL)",
+                         using: :btree)
+  end
+end

db/schema.rb

@@ -256,7 +256,6 @@ ActiveRecord::Schema.define(version: 20170921115009) do
   add_index "ci_builds", ["commit_id", "status", "type"], name: "index_ci_builds_on_commit_id_and_status_and_type", using: :btree
   add_index "ci_builds", ["commit_id", "type", "name", "ref"], name: "index_ci_builds_on_commit_id_and_type_and_name_and_ref", using: :btree
   add_index "ci_builds", ["commit_id", "type", "ref"], name: "index_ci_builds_on_commit_id_and_type_and_ref", using: :btree
-  add_index "ci_builds", ["id"], name: "index_for_ci_builds_retried_migration", where: "(retried IS NULL)", using: :btree
   add_index "ci_builds", ["project_id"], name: "index_ci_builds_on_project_id", using: :btree
   add_index "ci_builds", ["protected"], name: "index_ci_builds_on_protected", using: :btree
   add_index "ci_builds", ["runner_id"], name: "index_ci_builds_on_runner_id", using: :btree