anchor.diff:      ?assertEqual(ok, OciSession:ping()),
       SelStmt = OciSession:prep_sql("select * from dual"),
       ?assertEqual(ok, OciSession:ping()),
  -    ?assertEqual({cols,[{<<"DUMMY">>,'SQLT_CHR',1,0,0}]}, SelStmt:exec_stmt()),
  +    ?assertMatch({cols,[{<<"DUMMY">>,'SQLT_CHR',_,0,0}]}, SelStmt:exec_stmt()),
       ?assertEqual(ok, OciSession:ping()),
       ?assertEqual({{rows,[[<<"X">>]]},true}, SelStmt:fetch_rows(100)),
       ?assertEqual(ok, OciSession:ping()).
  
positive.code: 
      SelectStmt = OciSession:prep_sql(SelectSql),
      ?assertMatch({?PORT_MODULE, statement, _, _, _}, SelectStmt),
      ?assertEqual({cols, [{<<"NAME">>,'SQLT_CHR',30,0,0}
                          ,{<<"DAT">>,'SQLT_DAT',7,0,0}
                          ,{<<"TS">>,'SQLT_TIMESTAMP',11,0,6}
                          ,{<<"TSTZ">>,'SQLT_TIMESTAMP_TZ',13,0,6}
  
negative.code:     GoodSelect = <<"select 'abc' from dual">>,
      SelStmt = OciSession:prep_sql(GoodSelect),
      ?assertMatch({?PORT_MODULE, statement, _, _, _}, SelStmt),
      ?assertMatch({cols, [{<<"'ABC'">>,'SQLT_AFC',_,0,0}]}, SelStmt:exec_stmt()),
      ?assertEqual({{rows, [[<<"abc">>]]}, true}, SelStmt:fetch_rows(2)),
      ?assertEqual(ok, SelStmt:close()).
  
  