Added method to re-populating SiteStatitiscs counter

app/models/site_statistic.rb

@@ -49,7 +49,7 @@ class SiteStatistic < ActiveRecord::Base
   #
   # @return [SiteStatistic] record with tracked information
   def self.fetch
-    SiteStatistic.transaction(requires_new: true) do
+    transaction(requires_new: true) do
       SiteStatistic.first_or_create!
     end
   rescue ActiveRecord::RecordNotUnique
@@ -73,4 +73,18 @@ class SiteStatistic < ActiveRecord::Base
 
     super
   end
+
+  def self.recalculate_counters!
+    transaction do
+      # see https://gitlab.com/gitlab-org/gitlab-ce/issues/48967
+      ActiveRecord::Base.connection.execute('SET LOCAL statement_timeout TO 0') if Gitlab::Database.postgresql?
+      self.update_all('repositories_count = (SELECT COUNT(*) FROM projects)')
+    end
+
+    transaction do
+      # see https://gitlab.com/gitlab-org/gitlab-ce/issues/48967
+      ActiveRecord::Base.connection.execute('SET LOCAL statement_timeout TO 0') if Gitlab::Database.postgresql?
+      self.update_all('wikis_count = (SELECT COUNT(*) FROM project_features WHERE wiki_access_level != 0)')
+    end
+  end
 end

spec/models/site_statistic_spec.rb

@@ -80,4 +80,16 @@ describe SiteStatistic do
       end
     end
   end
+
+  describe '.recalculate_counters!' do
+    it 'recalculates existing counters' do
+      create(:project)
+      described_class.fetch.update(repositories_count: 0, wikis_count: 0)
+
+      described_class.recalculate_counters!
+
+      expect(described_class.fetch.repositories_count).to eq(1)
+      expect(described_class.fetch.wikis_count).to eq(1)
+    end
+  end
 end