Xsql workaround

Question

i'm trying to get the text frm a file using XSQL utility and BFILES.
Actually i have written a function finlob()which returns varchar2 .but when i run my xsql file i get the following error:
<xsql-error action="xsql:query"><statement>
select finlob() as aman from dual
</statement><message>ORA-06502: PL/SQL: numeric or value error: character string buffer too small
ORA-06512: at line 1
</message></xsql-error>
it seems as if there is something wrong with the internal buffer size which is a limit of oracle.
can u please help me with this problem.
the function which i use is as follows
RETURN VARCHAR2
IS
Lob_loc BFILE;
Buffer RAW(32767);
Amount BINARY_INTEGER := 10902;
Position BINARY_INTEGER := 1303;
AMANAM1 VARCHAR2(32767);
BEGIN
/* Select the LOB: */
SELECT filep INTO Lob_loc
FROM xdplob WHERE san='0000829901-98-000006';
dbms_output.enable(4000000);
/* Opening the BFILE: */
DBMS_LOB.OPEN (Lob_loc, DBMS_LOB.LOB_READONLY);
DBMS_LOB.READ (Lob_loc, Amount, Position, Buffer);
/* Display the buffer contents: */
AMANAM1 := utl_raw.cast_to_varchar2(Buffer);
RETURN AMANAM1;
/* Closing the BFILE: */
DBMS_LOB.CLOSE (Lob_loc);
EXCEPTION
WHEN NO_DATA_FOUND THEN
DBMS_OUTPUT.PUT_LINE('End of data');
END;
if i happen to use small value for Amount it works fine but with the current value(10902) it gives the error mentioned earlier.
it should work fine bcas the limit is 32767 and it is below the limit.?
any insight 'll be of great help
Thanx
Aman

Answer 1

This is not an XSQL issue.
It is an issue of the difference between the maximum length of a VARCHAR2 in PL/SQL and SQL.
If you create the following function:
create or replace function f(n number) return varchar2
is begin
return rpad('-',n,'-');
end;
Then, from the SQL*Plus command line you
can try:
SQL> select f(4000) from dual
which works fine since returning a
string of length 4000 from PL/SQL into
SQL (where the max length of a VARCHAR2
is 4000) is fine.
If you try...
SQL> select f(4001) from dual
You get your exact error above.
So, everything about your function
is working except that it's returning
a VARCHAR2 larger than 4000 characters
to SQL in the SELECT statement.