gitlab-org--gitlab-foss/db/migrate/20161017125927_add_unique_index_to_labels.rb
Jan Provaznik 0fc9f9d3e7 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
2018-11-22 13:18:28 +01:00

33 lines
1.4 KiB
Ruby

# rubocop:disable RemoveIndex
class AddUniqueIndexToLabels < ActiveRecord::Migration[4.2]
include Gitlab::Database::MigrationHelpers
DOWNTIME = true
DOWNTIME_REASON = 'This migration removes duplicated labels.'
disable_ddl_transaction!
def up
select_all('SELECT title, project_id, COUNT(id) as cnt FROM labels GROUP BY project_id, title HAVING COUNT(id) > 1').each do |label|
label_title = quote_string(label['title'])
duplicated_ids = select_all("SELECT id FROM labels WHERE project_id = #{label['project_id']} AND title = '#{label_title}' ORDER BY id ASC").map { |label| label['id'] }
label_id = duplicated_ids.first
duplicated_ids.delete(label_id)
execute("UPDATE label_links SET label_id = #{label_id} WHERE label_id IN(#{duplicated_ids.join(",")})")
execute("DELETE FROM labels WHERE id IN(#{duplicated_ids.join(",")})")
end
remove_index :labels, column: :project_id if index_exists?(:labels, :project_id)
remove_index :labels, column: :title if index_exists?(:labels, :title)
add_concurrent_index :labels, [:group_id, :project_id, :title], unique: true
end
def down
remove_index :labels, column: [:group_id, :project_id, :title] if index_exists?(:labels, [:group_id, :project_id, :title], unique: true)
add_concurrent_index :labels, :project_id
add_concurrent_index :labels, :title
end
end