Koh-kghu sessi,pl/sql vc2

Question

hi
i am trying the blow code ..and getting error ...
we have 10g databse
can anybody please explain ...what is this all about
SQL> ed
Wrote file afiedt.buf
  1  declare
  2  a varchar(4000);
  3  b long raw;
  4  cursor c1 is select databuf from long_raw_table;
  5  begin
  6  open c1;
  7  loop
  8  fetch c1 into b ;
  9  exit when c1%notfound;
10  a:=UTL_RAW.CAST_TO_VARCHAR2(b);
11  dbms_output.put_line(a);
12  end loop;
13* end;
SQL> /
PL/SQL procedure successfully completed.
SQL> set serveroutput on
SQL> /
declare
ERROR at line 1:
ORA-04030: out of process memory when trying to
allocate 16396 bytes (koh-kghu sessi,pl/sql vc2)

Answer 1

hemu wrote:
can anybody please explain ...what is this all aboutUsing DBMS_OUTPUT. It is not a write-to-screen routine. It is a database package that uses PGA memory. Writing to DBMS_OUTPUT means putting data into its buffer variable.
When the client call has completed, the client can then interrogate this buffer variable and display the contents.
Your code is "writing" chunks of data into this buffer variable - that consumes server memory. It also consumes the most expensive of server memory - private and non-shared process memory. How much data is your code "writing" via DBMS_OUTPUT into this PL/SQL buffer variable? 100MB? 500MB? 1GB? More?
Do you really think that this is a scalable and effective approach to get data from the database and passing that to a client - using expensive PGA memory as a buffer area?