diff options
Diffstat (limited to 'db/post_migrate/20200526115436_dedup_mr_metrics.rb')
-rw-r--r-- | db/post_migrate/20200526115436_dedup_mr_metrics.rb | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/db/post_migrate/20200526115436_dedup_mr_metrics.rb b/db/post_migrate/20200526115436_dedup_mr_metrics.rb new file mode 100644 index 00000000000..d2660504939 --- /dev/null +++ b/db/post_migrate/20200526115436_dedup_mr_metrics.rb @@ -0,0 +1,65 @@ +# frozen_string_literal: true + +class DedupMrMetrics < ActiveRecord::Migration[6.0] + include Gitlab::Database::MigrationHelpers + + DOWNTIME = false + TMP_INDEX_NAME = 'tmp_unique_merge_request_metrics_by_merge_request_id' + INDEX_NAME = 'unique_merge_request_metrics_by_merge_request_id' + + disable_ddl_transaction! + + class MergeRequestMetrics < ActiveRecord::Base + self.table_name = 'merge_request_metrics' + + include EachBatch + end + + def up + last_metrics_record_id = MergeRequestMetrics.maximum(:id) || 0 + + # This index will disallow further duplicates while we're deduplicating the data. + add_concurrent_index(:merge_request_metrics, :merge_request_id, where: "id > #{Integer(last_metrics_record_id)}", unique: true, name: TMP_INDEX_NAME) + + MergeRequestMetrics.each_batch do |relation| + duplicated_merge_request_ids = MergeRequestMetrics + .where(merge_request_id: relation.select(:merge_request_id)) + .select(:merge_request_id) + .group(:merge_request_id) + .having('COUNT(merge_request_metrics.merge_request_id) > 1') + .pluck(:merge_request_id) + + duplicated_merge_request_ids.each do |merge_request_id| + deduplicate_item(merge_request_id) + end + end + + add_concurrent_index(:merge_request_metrics, :merge_request_id, unique: true, name: INDEX_NAME) + remove_concurrent_index_by_name(:merge_request_metrics, TMP_INDEX_NAME) + end + + def down + remove_concurrent_index_by_name(:merge_request_metrics, TMP_INDEX_NAME) + remove_concurrent_index_by_name(:merge_request_metrics, INDEX_NAME) + end + + private + + def deduplicate_item(merge_request_id) + merge_request_metrics_records = MergeRequestMetrics.where(merge_request_id: merge_request_id).order(updated_at: :asc).to_a + + attributes = {} + merge_request_metrics_records.each do |merge_request_metrics_record| + params = merge_request_metrics_record.attributes.except('id') + attributes.merge!(params.compact) + end + + ActiveRecord::Base.transaction do + record_to_keep = merge_request_metrics_records.pop + records_to_delete = merge_request_metrics_records + + MergeRequestMetrics.where(id: records_to_delete.map(&:id)).delete_all + record_to_keep.update!(attributes) + end + end +end |