diff --git a/lib/modules/Sql.pmod/pgsql.pike b/lib/modules/Sql.pmod/pgsql.pike
index c9fc00c9a7ef01065aeb9a95a7f9b0891639c472..9867f4a403b22e06e0935192d8a41638fa7799ac 100644
--- a/lib/modules/Sql.pmod/pgsql.pike
+++ b/lib/modules/Sql.pmod/pgsql.pike
@@ -1282,7 +1282,7 @@ protected void destroy() {
    */
   if (err || (err = catch(errstring = error(1))))
     werror(describe_backtrace(err));
-  else if (sizeof(errstring))
+  else if (errstring && sizeof(errstring))
     werror(errstring);
 }