[bug] regenerate statistics does not remove all previous values

CHANGELOG.md

@@ -9,6 +9,7 @@
 - Fix a bug: in invoice configuration panel, VAT amount and total excl. taxes are inverted
 - Fix a bug: unable to compute user's age when they were born on february 29th and current year is not a leap year
 - Fix a bug: wrong statistics about hours available for machines reservation. Fix requires user action (1)
+- Fix a bug: when regenerating statistics, previous values are not fully removed (only 10 firsts), resulting in wrong statistics generation
 - [TODO DEPLOY] remove possible value `application/` in `ALLOWED_MIME_TYPES` list, in environment variable
 - [TODO DEPLOY] `rails runner StatisticCustomAggregation.destroy_all`, then `rake db:seed`, then `rake fablab:es_build_availabilities_index` (1)
 

app/services/statistic_service.rb

@@ -297,8 +297,10 @@ class StatisticService
   end
 
   def clean_stat(options = default_options)
+    client = Elasticsearch::Model.client
     %w{Account Event Machine Project Subscription Training User}.each do |o|
-      "Stats::#{o}".constantize.search(query: {match: {date: format_date(options[:start_date])}}).results.each(&:destroy)
+      model = "Stats::#{o}".constantize
+      client.delete_by_query(index: model.index_name, type: model.document_type, body: {query: {match: {date: format_date(options[:start_date])}}})
     end
   end