SQL & PL/SQL

Hello all.

I'm getting an error on a trigger.

It's the common error...

ORA-04098: trigger 'string' is invalid and failed re-validation..

And this is what happened when I tried to compile.

SQL> alter trigger schema.trigger_name compile;
Warning: Trigger altered with compilation errors.
SQL>show err;
No errors.
SQL> show errors trigger trigger_name;
No errors.

How can I see the errors during compilation?

Thanks.
Alex.