Merge branch 'add_existing_column_check_to_46532' into 'master'

Guard against existence of project_features.requirement_access_level

See merge request gitlab-org/gitlab!47458

changelogs/unreleased/add_existing_column_check_to_46532.yml

+---
+title: Guard against existence of project_features.requirement_access_level in migration
+merge_request: 47458
+author: Lee Tickett
+type: other

db/migrate/20201030092151_add_requirements_access_level_to_project_features.rb

@@ -6,14 +6,14 @@ class AddRequirementsAccessLevelToProjectFeatures < ActiveRecord::Migration[6.0]
   DOWNTIME = false
 
   def up
-    with_lock_retries do
-      add_column :project_features, :requirements_access_level, :integer, default: 20, null: false
+    unless column_exists?(:project_features, :requirements_access_level)
+      with_lock_retries { add_column :project_features, :requirements_access_level, :integer, default: 20, null: false }
     end
   end
 
   def down
-    with_lock_retries do
-      remove_column :project_features, :requirements_access_level, :integer
+    if column_exists?(:project_features, :requirements_access_level)
+      with_lock_retries { remove_column :project_features, :requirements_access_level }
     end
   end
 end