public void Split__trg__nth__new(Split_ctx ctx, Db_conn trg_conn) {
   if (cur_ns_id != ctx.Trg_ns()) {
     if (cur_ns_id != -1) bldr.Exec_qry_end();
     cur_ns_id = ctx.Trg_ns();
     bldr.Exec_qry_bgn(Rndm_qry_itm.New_by_ns(ctx.Wiki(), cur_ns_id));
   }
   bldr.Exec_rng_bgn();
   bldr.Conn().Txn_bgn("rndm");
 }
 public void Split__term(Split_ctx ctx) {
   bldr.Exec_qry_end();
 }