class FixupEnvironmentNameUniqueness < ActiveRecord::Migration[4.2] include Gitlab::Database::ArelMethods include Gitlab::Database::MigrationHelpers DOWNTIME = true DOWNTIME_REASON = 'Renaming non-unique environments' def up environments = Arel::Table.new(:environments) # Get all [project_id, name] pairs that occur more than once finder_sql = environments .group(environments[:project_id], environments[:name]) .having(Arel.sql("COUNT(1)").gt(1)) .project(environments[:project_id], environments[:name]) .to_sql conflicting = connection.exec_query(finder_sql) conflicting.rows.each do |project_id, name| fix_duplicates(project_id, name) end end def down # Nothing to do end # Rename conflicting environments by appending "-#{id}" to all but the first def fix_duplicates(project_id, name) environments = Arel::Table.new(:environments) finder_sql = environments .where(environments[:project_id].eq(project_id)) .where(environments[:name].eq(name)) .order(environments[:id].asc) .project(environments[:id], environments[:name]) .to_sql # Now we have the data for all the conflicting rows conflicts = connection.exec_query(finder_sql).rows conflicts.shift # Leave the first row alone conflicts.each do |id, name| update_sql = arel_update_manager .table(environments) .set(environments[:name] => name + "-" + id.to_s) .where(environments[:id].eq(id)) .to_sql connection.exec_update(update_sql, self.class.name, []) end end end