gitlab-org--gitlab-foss/db/migrate/20170619144837_add_index_fo...

class AddIndexForHeadPipelineMergeRequest < ActiveRecord::Migration[4.2]
  include Gitlab::Database::MigrationHelpers

  DOWNTIME = false

  disable_ddl_transaction!

  def up
    add_concurrent_index :merge_requests, :head_pipeline_id
  end

  def down
    remove_concurrent_index :merge_requests, :head_pipeline_id if index_exists?(:merge_requests, :head_pipeline_id)
  end
end
Add version 4.2 to all existing migrations DB schema generated by a migration may look different in rails 4 and 5 (because rails 5 may use different default values). For this reason it's important to explicitly set for which rails version a migration was written for. See https://stackoverflow.com/questions/35929869/activerecordmigration-deprecation-warning-asks-for-rails-version-but-im-no/35930912#35930912 2018-11-13 07:27:31 +00:00			`class AddIndexForHeadPipelineMergeRequest < ActiveRecord::Migration[4.2]`
Add index for head pipeline id 2017-06-19 14:52:57 +00:00			`include Gitlab::Database::MigrationHelpers`

			`DOWNTIME = false`

			`disable_ddl_transaction!`

			`def up`
			`add_concurrent_index :merge_requests, :head_pipeline_id`
			`end`

			`def down`
			`remove_concurrent_index :merge_requests, :head_pipeline_id if index_exists?(:merge_requests, :head_pipeline_id)`
			`end`
			`end`