Create Validation

Code Editor PL/SQL Function Body Returning Error Test:

declare
v_test varchar2(50);
begin
select last_name into v_test from employees where last_name= :P4_LAST_NAME ;
if
v_test IS  NULL then
return null ;
else
return 'This name is not available' ;
end if;
exception
when others then
return null ;
end ;