2 files changed, 17 insertions, 3 deletions
diff --git a/perllib/FixMyStreet/App/Controller/Report.pm b/perllib/FixMyStreet/App/Controller/Report.pm
index 5c64bd9e5..acc6f9a09 100644
--- a/perllib/FixMyStreet/App/Controller/Report.pm
+++ b/perllib/FixMyStreet/App/Controller/Report.pm
@@ -325,7 +325,7 @@ sub inspect : Private {
         my %update_params = ();
 
         if ($permissions->{report_inspect}) {
-            foreach (qw/detailed_information traffic_information duplicate_of/) {
+            foreach (qw/detailed_information traffic_information/) {
                 $problem->set_extra_metadata( $_ => $c->get_param($_) );
             }
 
@@ -360,7 +360,10 @@ sub inspect : Private {
             }
             if ( $problem->state ne 'duplicate' ) {
                 $problem->unset_extra_metadata('duplicate_of');
+            } elsif (my $duplicate_of = $c->get_param('duplicate_of')) {
+                $problem->set_duplicate_of($duplicate_of);
             }
+
             if ( $problem->state ne $old_state ) {
                 $c->forward( '/admin/log_edit', [ $problem->id, 'problem', 'state_change' ] );
 
diff --git a/perllib/FixMyStreet/DB/Result/Problem.pm b/perllib/FixMyStreet/DB/Result/Problem.pm
index a12f8c20d..720e8cc93 100644
--- a/perllib/FixMyStreet/DB/Result/Problem.pm
+++ b/perllib/FixMyStreet/DB/Result/Problem.pm
@@ -1115,6 +1115,16 @@ has shortlisted_user => (
     },
 );
 
+sub set_duplicate_of {
+    my ($self, $other_id) = @_;
+    $self->set_extra_metadata( duplicate_of => $other_id );
+    my $dupe = $self->result_source->schema->resultset("Problem")->find($other_id);
+    my $dupes_duplicates = $dupe->get_extra_metadata('duplicates') || [];
+    push @$dupes_duplicates, $self->id;
+    $dupe->set_extra_metadata( duplicates => $dupes_duplicates );
+    $dupe->update;
+}
+
 has duplicate_of => (
     is => 'ro',
     lazy => 1,
@@ -1132,8 +1142,9 @@ has duplicates => (
     lazy => 1,
     default => sub {
         my $self = shift;
-        my $rabx_id = RABX::serialise( $self->id );
-        my @duplicates = $self->result_source->schema->resultset('Problem')->search({ extra => { like => "\%duplicate_of,$rabx_id%" } })->all;
+        my $duplicates = $self->get_extra_metadata("duplicates") || [];
+        return [] unless $duplicates && @$duplicates;
+        my @duplicates = $self->result_source->schema->resultset('Problem')->search({ id => $duplicates })->all;
         return \@duplicates;
     },
 );