How to select data(first 10 charcters) from a LONG datatype column.?

Question

Hi,
I am getting below error wile i am trying to select forst 10 charcter from a log datatype column. May be I am using it in a wrong way using SUBSTR function.
I dont know whether SUBSTR works for LONG columns or not as it's char function.
I am not able to find any inbuild conversion function which will work like TO_CHAR.Please revert.
My steps:-
=================================================
SQL> create table long_varchartest(
2 nirav long, sangram varchar2(30));
Table created.
SQL> insert into long_varchartest values('ns89027','sd22712');
1 row created.
SQL> insert into long_varchartest values('Nirav Shah', 'Sangram Dash');
1 row created.
SQL> commit;
Commit complete.
SQL> select * from long_varchartest;
NIRAV SANGRAM
ns89027 sd22712
Nirav Shah Sangram Dash
SQL> insert into long_varchartest(sangram)
2 select nirav from long_varchartest;
select nirav from long_varchartest
ERROR at line 2:
ORA-00997: illegal use of LONG datatype

Answer 1

declare
l_text varchar2(4000) ;
begin
  select nirav into l_text from  long_varchartest where sangram = 'sd22712';
  dbms_output.put_line(substr(l_text,1,10)); 
end ;you could also follow this link [http://www.oracle.com/technology/oramag/code/tips2003/052503.html]