Search notes:

ORA-01858: A non-numeric character was found instead of a numeric character

The following statement throws ORA-01858: A non-numeric character was found instead of a numeric character.
select
   to_date('no such date', 'dd.mm.yyyy')
from
   dual;
This error can be prevented by using the default null on conversion error clause:
select
   to_date('no such date' default null on conversion error, 'dd.mm.yyyy')
from
   dual;

See also

Other Oracle error messages such as ORA-43918: This argument must be a literal

Index