debian-mirror-gitlab/db/post_migrate/20200526115436_dedup_mr_metrics.rb
2020-08-09 17:44:08 +05:30

66 lines
2.2 KiB
Ruby

# 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