lib/PublicInbox/Over.pm | 8 ++++----

diff --git a/lib/PublicInbox/Over.pm b/lib/PublicInbox/Over.pm
index 786f9d922282ea3358c7664462ceb8b591d05e4d..d6409b2a5fdb2017a69344aed92e60be77b2eb44 100644
--- a/lib/PublicInbox/Over.pm
+++ b/lib/PublicInbox/Over.pm
@@ -273,13 +273,13 @@ 	return $rows if $raw;
 	my $eidx_key_sth = $dbh->prepare_cached(<<'', undef, 1);
 SELECT eidx_key FROM inboxes WHERE ibx_id = ?
 
-	[ map {
-		my $r = $_;
+	for my $r (@$rows) {
 		$eidx_key_sth->execute($r->[0]);
 		my $eidx_key = $eidx_key_sth->fetchrow_array;
 		$eidx_key //= "missing://ibx_id=$r->[0]";
-		"$eidx_key:$r->[1]:".unpack('H*', $r->[2]);
-	} @$rows ];
+		$r = "$eidx_key:$r->[1]:".unpack('H*', $r->[2]);
+	}
+	$rows;
 }
 
 sub next_by_mid {