Rake task to check and remove duplicate rent periods

lib/tasks/duplicate_rent_periods.rake

@@ -0,0 +1,53 @@
+desc "Find and output each group of duplicate rent periods with a total count"
+task find_redundant_rent_periods: :environment do
+  duplicate_groups = OrganisationRentPeriod
+                       .select('organisation_id, rent_period')
+                       .group('organisation_id, rent_period')
+                       .having('COUNT(*) > 1')
+
+  duplicate_records = OrganisationRentPeriod
+                        .where(organisation_id: duplicate_groups.map(&:organisation_id), rent_period: duplicate_groups.map(&:rent_period))
+
+  duplicate_groups.each do |group|
+    group_records = duplicate_records.where(organisation_id: group.organisation_id, rent_period: group.rent_period)
+    group_records.each do |record|
+      puts "ID: #{record.id}, Organisation ID: #{record.organisation_id}, Rent Period: #{record.rent_period}"
+    end
+    puts "----------------------"
+  end
+
+  ids_to_keep = OrganisationRentPeriod
+                  .select('MIN(id) as id')
+                  .group('organisation_id, rent_period')
+                  .having('COUNT(*) > 1')
+                  .map(&:id)
+
+  redundant_ids = duplicate_records.pluck(:id) - ids_to_keep
+
+  puts "Number of duplicate records: #{redundant_ids.size}"
+  puts "Number of records to keep: #{ids_to_keep.size}"
+end
+
+desc "Delete redundant rent periods"
+task delete_duplicate_rent_periods: :environment do
+  duplicate_groups = OrganisationRentPeriod
+                       .select('organisation_id, rent_period')
+                       .group('organisation_id, rent_period')
+                       .having('COUNT(*) > 1')
+
+  duplicate_ids = OrganisationRentPeriod
+                    .where(organisation_id: duplicate_groups.map(&:organisation_id), rent_period: duplicate_groups.map(&:rent_period))
+                    .pluck(:id)
+
+  ids_to_keep = OrganisationRentPeriod
+                  .select('MIN(id) as id')
+                  .group('organisation_id, rent_period')
+                  .having('COUNT(*) > 1')
+                  .map(&:id)
+
+  redundant_ids = duplicate_ids - ids_to_keep
+
+  OrganisationRentPeriod.where(id: redundant_ids).delete_all
+
+  puts "Number of deleted duplicate records: #{redundant_ids.size}"
+end