MT#8371 Optimize select actual billing_mappings with virtual view

lib/NGCP/Schema/Result/billing_mappings_actual.pm

@@ -0,0 +1,70 @@
+package NGCP::Schema::Result::billing_mappings_actual;
+use Scalar::Util qw(blessed);
+use base qw/DBIx::Class::Core/;
+
+our $VERSION = '2.007';
+
+__PACKAGE__->load_components(
+  "InflateColumn::DateTime",
+  "Helper::Row::ToJSON",
+  "+NGCP::Schema::InflateColumn::DateTime::EpochMicro",
+);
+__PACKAGE__->table_class('DBIx::Class::ResultSource::View');
+__PACKAGE__->table("billing_mappings_actual");
+
+
+__PACKAGE__->add_columns(
+  "actual_bm_id",
+  {
+    data_type => "integer",
+    extra => { unsigned => 1 },
+    is_auto_increment => 1,
+    is_nullable => 0,
+  },
+  "contract_id",
+  {
+    data_type => "integer",
+    extra => { unsigned => 1 },
+    is_foreign_key => 1,
+    is_nullable => 0,
+  },
+);
+__PACKAGE__->belongs_to(
+  "contract",
+  "NGCP::Schema::Result::contracts",
+  { id => "contract_id" },
+  { is_deferrable => 1, on_delete => "CASCADE", on_update => "CASCADE" },
+);
+
+__PACKAGE__->has_many(
+  "billing_mappings",
+  "NGCP::Schema::Result::billing_mappings",
+  { "foreign.id" => "self.actual_bm_id" },
+  { cascade_copy => 0, cascade_delete => 0 },
+);
+
+__PACKAGE__->set_primary_key("actual_bm_id");
+
+sub TO_JSON {
+    my ($self) = @_;
+    return {
+        map { blessed($_) && $_->isa('DateTime') ? $_->datetime : $_ } %{ $self->next::method }
+    };
+}
+
+__PACKAGE__->result_source_instance->is_virtual(1);
+
+__PACKAGE__->result_source_instance->view_definition("
+select bm.contract_id,max(bm.id) as actual_bm_id from billing.billing_mappings bm 
+    inner join 
+        (select bmm.contract_id, max(bmm.start_date) max_start_date 
+        from billing.billing_mappings bmm 
+        where ( bmm.`end_date` >= ? OR bmm.`end_date` IS NULL ) 
+        AND ( bmm.`start_date` <= ? OR bmm.`start_date` IS NULL ) 
+        group by bmm.contract_id
+    ) bmm on bm.contract_id=bmm.contract_id and (bm.start_date=bmm.max_start_date or bmm.max_start_date is null) 
+group by  bm.contract_id
+");
+
+1;
+

lib/NGCP/Schema/Result/contracts.pm

@@ -119,6 +119,12 @@ __PACKAGE__->has_many(
   { "foreign.contract_id" => "self.id" },
   { cascade_copy => 0, cascade_delete => 0 },
 );
+__PACKAGE__->has_many(
+  "billing_mappings_actual",
+  "NGCP::Schema::Result::billing_mappings_actual",
+  { "foreign.contract_id" => "self.id" },
+  { cascade_copy => 0, cascade_delete => 0 },
+);
 
 __PACKAGE__->belongs_to(
   "contact",