text: select SUBDATE(SYSDATE, 9999999);
  select SUBDATE(SYSDATE, -9999999);
  
  SELECT SUBDATE(DATE '2008-12-25', 9999), SUBDATE(DATE '2008-12-25',2999999);
  SELECT SUBDATE(DATE '2008-12-25', -19999), SUBDATE(DATE '2008-12-25',19999);
  
  SELECT SUBDATE(DATE '2008-12-25', 99), SUBDATE(DATE '2008-12-25',99);
  SELECT SUBDATE(DATE '2008-12-25', -99999), SUBDATE(DATE '2008-12-25',-99999);
  
  SELECT SUBDATE(DATE '2008-12-25', 256), SUBDATE(DATE '2008-12-25',256);
  SELECT SUBDATE(DATE '2008-12-25', -256), SUBDATE(DATE '2008-12-25',-256);
  
  
  SELECT SUBDATE(DATE '2008-12-25', 256), SUBDATE(DATE '2008-12-25',-256),SUBDATE(DATE '2008-12-25',-1024),SUBDATE(DATE '2008-12-25',1024);
  
  SELECT SUBDATE(DATE '2008-12-25', 256), SUBDATE(DATE '2008-12-25',-256),SUBDATE(DATE '2008-12-25',-1024),SUBDATE(DATE '2008-12-25',1024), SUBDATE(DATE '2008-12-25',-256),SUBDATE(DATE '2008-12-25',-1024),SUBDATE(DATE '2008-12-25',1024);
  
  SELECT SUBDATE(DATE '2008-12-25', 256), SUBDATE(DATE '2008-12-25',-256),SUBDATE(DATE '2008-12-25',-1024),SUBDATE(DATE '2008-12-25',1024), SUBDATE(DATE '2008-12-25',-256),SUBDATE(DATE '2008-12-25',-1024),SUBDATE(DATE '2008-12-25',1024), SUBDATE(DATE '2008-12-25',-256),SUBDATE(DATE '2008-12-25',-1024),SUBDATE(DATE '2008-12-25',1024), SUBDATE(DATE '2008-12-25',-256),SUBDATE(DATE '2008-12-25',-1024),SUBDATE(DATE '2008-12-25',1024), SUBDATE(DATE '2008-12-25',-256),SUBDATE(DATE '2008-12-25',-1024),SUBDATE(DATE '2008-12-25',1024), SUBDATE(DATE '2008-12-25',-256),SUBDATE(DATE '2008-12-25',-1024),SUBDATE(DATE '2008-12-25',1024), SUBDATE(DATE '2008-12-25',-256),SUBDATE(DATE '2008-12-25',-1024),SUBDATE(DATE '2008-12-25',1024), SUBDATE(DATE '2008-12-25',-256),SUBDATE(DATE '2008-12-25',-1024),SUBDATE(DATE '2008-12-25',1024);
  
  drop table if exists t1
  create table t1(id int primary key, col1 datetime default SYSDATETIME unique, col2 datetime default SYSDATETIME not null, col3 datetime default SYSDATETIME, col4 datetime default SYSDATETIME);
  
  insert into t1 values(1, datetime'12/12/2000 12:12:12.123', '12/12/2000 12:12:12.123', '12/12/2000 12:12:12.123', '12/12/2000 12:12:12.123');
  insert into t1 values(2, datetime'11/11/2000 11:11:11.123', '11/11/2000 11:11:11.123', '11/11/2000 11:11:11.123', '11/11/2000 11:11:11.123');
  insert into t1 values(3, datetime'10/10/2000 10:10:10.123', '10/10/2000 10:10:10.123', '10/10/2000 10:10:10.123', '10/10/2000 10:10:10.123');
  insert into t1 values(4, datetime'09/09/2000 09:09:09.123', '09/09/2000 09:09:09.123', '09/09/2000 09:09:09.123', '09/09/2000 09:09:09.123');
  insert into t1 values(5, datetime'08/08/2000 08:08:08.123', '08/08/2000 08:08:08.123', '08/08/2000 08:08:08.123', '08/08/2000 08:08:08.123');
  SELECT SUBDATE(col1, 18) from t1 where t1.id = 333;
  SELECT SUBDATE(col4, -999) from t1 order by t1.id ;
  
  
  drop table t1;
  