empty table

desc t1;               
---------------------------------------------
COL1                          DATE
COL2                          VARCHAR2(1000 BYTE)
COL3                          VARCHAR2(25 BYTE)

explain plan for 
select * from t1;
select * from table(dbms_xplan.display);
--------------------------------------------------------------------------------------
| Id  | Operation         | Name             | Rows  | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |                  |     1 |   525 |  9078   (1)| 00:01:49 |
|   1 |  TABLE ACCESS FULL| SYNC_ERROR_MONTH |     1 |   525 |  9078   (1)| 00:01:49 |
--------------------------------------------------------------------------------------

explain plan for 
select * from t2;
select * from table(dbms_xplan.display);
---------------------------------------------------------------------------------------
| Id  | Operation         | Name              | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |                   |     1 |   525 |     2   (0)| 00:00:01 |
|   1 |  TABLE ACCESS FULL| SYNC_ERROR_MONTH2 |     1 |   525 |     2   (0)| 00:00:01 |
---------------------------------------------------------------------------------------

select * from dba_segments where segment_name in ('T1', 'T2');

select * from dba_segments where segment_name in ('T1', 'T2');

select * from T1;
Exec time: 9,156 sec

select * from T2;
Exec time: 0,047 sec