User defined function and returning resultset

Question

Hi all,
Following query, if I comment the statement in where clause which refers to a returning value of a function in the subquery, it takes 1 sec to finish. when uncomment it however, can't finish in 30 mins. Please help me on finding out the problem.
I'm also wondering how to get a returning cursor in this case(to bypass above trouble)..
Many thanks
-s
--pseudocode for how can I get a cursor in an anonymous block for host app
begin
-- get the resultset1 in someway
select t1.showit,...
from t1..;
-- based on resultset1
open myrefcursor for
select * from resultset1 -- what is the resultset1?
where resultset1.showit=1;
end;
--end pseudocode for getting a cursor
-- hanging(takes too long) query (simplified)
select t1.*,t2.account,t2.showit
from (select t3.account,myfunc(t3.account) showit
from tbl2 t3) t2,
tbl1 t1
where t1.account=t2.account
and ...
/* "hang" this query by uncomment this */
-- and t2.showit=1;
-- functions
function myfunc(p_acc varchar2)
return number is
v_tmpdate date;
v_invdate date;
v_tmpcount number(8);
v_accid number(8);
v_curodisp number(14,4);
v_curdisp number(14,4);
v_curdisprev number(14,4);
v_rowcount number(8);
v_tmpshow number(8);
p_vkey number(8);
p_inv varchar(50);
cursor cur(cv_vkey number, cv_accid number, cv_lastdate date) is
select a.vkey vkey,a.invdate invdate, b.odisp odisp
from inv a, recon b
where a.vkey=cv_vkey
and a.akey = cv_accid
and a.invdate between to_date('01/01/2000','DD/MM/YYYY')
and cv_lastdate
and b.vkey = a.vkey
and b.inv# = a.inv#
order by invdate DESC;
begin
select vkey,inv#,akey, invdate into p_vkey,p_inv,v_accid, v_invdate
from inv
where akey = p_acc;
v_tmpdate := add_months(v_invdate, 1);
select count(*) into v_tmpcount
from recon a, inv b
where b.vkey = p_vkey
and b.akey = v_accid
and b.invdate between to_date('01/01/2000','DD/MM/YYYY')
and v_tmpdate
and a.inv# = b.inv#
and a.vkey = b.vkey;
if v_tmpcount = 0 then
return 0;
end if;
v_rowcount := 0;
for c1 in cur(p_vkey,v_accid,v_tmpdate) loop
v_rowcount := v_rowcount + 1;
v_curdisp := getcurdisp(c1.vkey,c1.inv#);
v_curdisprev := getcurdisprev(c1.vkey,c1.inv#);
v_curodisp := nvl(c1.odisp, 0) - v_curdisp - v_curdisprev;
if v_curodisp >= 1000 then
return 1;
elsif v_curodisp = 0 then
return 0;
end If;
end if;
if extract(month from c1.invdate) in ('1','01')
and extract(year from c1.invdate) = '2000' then
select a.showodisp into v_tmpshow
from acc a, inv b
where b.vkey = c1.vkey
and b.inv# = c1.inv#
and a.akey = b.akey;
return v_tmpshow;
end If;
end loop;
return 0;
end myfunc;
function getcurdisp(p_vkey,p_inv)
return number is
v_tmp number(15,4);
begin
select sum(amount) into v_tmp
from cost
where vkey=p_vkey
and inv#=p_inv
and desc like '%disp';
return v_tmp;
end;
function getcurdisprev(p_vkey,p_inv)
return number is
v_tmp number(15,4);
begin
select sum(amount) into v_tmp
from cost
where vkey=p_vkey
and inv#=p_inv
and desc like '%disprev';
return v_tmp;
end;

Answer 1

Autotrace only showed the index usage on the main query, but nothing on the queries within the functions, so here is the tkprof that shows index usage on the queries within the functions.
TKPROF: Release 9.2.0.1.0 - Production on Mon Jan 17 00:31:39 2005
Copyright (c) 1982, 2002, Oracle Corporation.  All rights reserved.
Trace file: ora92_ora_4092.trc
Sort options: default
count    = number of times OCI procedure was executed
cpu      = cpu time in seconds executing
elapsed  = elapsed time in seconds executing
disk     = number of physical reads of buffers from disk
query    = number of buffers gotten for consistent read
current  = number of buffers gotten in current mode (usually for update)
rows     = number of rows processed by the fetch or execute call
alter session set sql_trace=true
call     count       cpu    elapsed       disk      query    current        rows
Parse        0      0.00       0.00          0          0          0           0
Execute      1      0.00       0.00          0          0          0           0
Fetch        0      0.00       0.00          0          0          0           0
total        1      0.00       0.00          0          0          0           0
Misses in library cache during parse: 0
Optimizer goal: CHOOSE
Parsing user id: 59 
select t1.*, t2.account, t2.showit
from   tbl1 t1,
       (select account, myfunc(account) showit
        from   tbl2) t2
where  t1.account = t2.account
and    t2.showit = 1
call     count       cpu    elapsed       disk      query    current        rows
Parse        1      0.00       0.00          0          0          0           0
Execute      1      0.00       0.00          0          0          0           0
Fetch        1      0.11       1.81          0          1          0           0
total        3      0.11       1.81          0          1          0           0
Misses in library cache during parse: 0
Optimizer goal: CHOOSE
Parsing user id: 59 
Rows     Row Source Operation
      0  NESTED LOOPS 
      0   INDEX FULL SCAN OBJ#(69662) (object id 69662)
      0   INDEX RANGE SCAN OBJ#(69661) (object id 69661)
select user#
from
sys.user$ where name = 'OUTLN'
call     count       cpu    elapsed       disk      query    current        rows
Parse        1      0.00       0.00          0          0          0           0
Execute      1      0.00       0.00          0          0          0           0
Fetch        1      0.00       0.00          0          2          0           1
total        3      0.00       0.00          0          2          0           1
Misses in library cache during parse: 0
Optimizer goal: CHOOSE
Parsing user id: SYS   (recursive depth: 2)
Rows     Row Source Operation
      1  TABLE ACCESS BY INDEX ROWID USER$
      1   INDEX UNIQUE SCAN I_USER1 (object id 44)
select a.vkey, a.invdate, b.odisp, a.inv#
     from   inv a, recon b
     where  a.akey = :b1
     and    a.invdate between to_date ('01/01/2000', 'DD/MM/YYYY')
                      and     add_months (a.invdate, 1)
     and    b.vkey = a.vkey
     and    b.inv# = a.inv#
     order  by a.invdate DESC
call     count       cpu    elapsed       disk      query    current        rows
Parse        1      0.00       0.10          0          0          0           0
Execute    105      0.00       0.01          0          0          0           0
Fetch      105      0.01       0.01          0        309          0         100
total      211      0.01       0.13          0        309          0         100
Misses in library cache during parse: 1
Optimizer goal: CHOOSE
Parsing user id: 59     (recursive depth: 1)
Rows     Row Source Operation
    100  SORT ORDER BY
    104   TABLE ACCESS BY INDEX ROWID RECON
    313    NESTED LOOPS 
    104     INDEX FULL SCAN INV_IDX (object id 69658)
    104     INDEX RANGE SCAN RECON_IDX (object id 69659)
SELECT sum (amount)
  from   cost
  where  vkey = :b2
  and    inv# = :b1
  and    descr like '%disp'
call     count       cpu    elapsed       disk      query    current        rows
Parse        1      0.00       0.00          0          0          0           0
Execute    100      0.00       0.00          0          0          0           0
Fetch      100      0.01       0.00          0        100          0         100
total      201      0.01       0.01          0        100          0         100
Misses in library cache during parse: 1
Optimizer goal: CHOOSE
Parsing user id: 59     (recursive depth: 1)
Rows     Row Source Operation
    100  SORT AGGREGATE
      0   TABLE ACCESS BY INDEX ROWID COST
      0    INDEX RANGE SCAN COST_IDX (object id 69657)
SELECT sum (amount)
  from   cost
  where  vkey = :b2
  and    inv# = :b1
  and    descr like '%disprev'
call     count       cpu    elapsed       disk      query    current        rows
Parse        1      0.00       0.00          0          0          0           0
Execute    100      0.00       0.00          0          0          0           0
Fetch      100      0.01       0.00          0        100          0         100
total      201      0.01       0.01          0        100          0         100
Misses in library cache during parse: 1
Optimizer goal: CHOOSE
Parsing user id: 59     (recursive depth: 1)
Rows     Row Source Operation
    100  SORT AGGREGATE
      0   TABLE ACCESS BY INDEX ROWID COST
      0    INDEX RANGE SCAN COST_IDX (object id 69657)
SELECT a.showodisp
      from   acc a, inv b
      where  b.vkey = :b2
      and    b.inv# = :b1
      and    a.akey = b.akey
call     count       cpu    elapsed       disk      query    current        rows
Parse        1      0.00       0.00          0          0          0           0
Execute    100      0.01       0.00          0          0          0           0
Fetch      100      0.03       0.00          0        299          0          99
total      201      0.04       0.01          0        299          0          99
Misses in library cache during parse: 1
Optimizer goal: CHOOSE
Parsing user id: 59     (recursive depth: 1)
Rows     Row Source Operation
     99  TABLE ACCESS BY INDEX ROWID ACC
    299   NESTED LOOPS 
    100    INDEX RANGE SCAN INV_IDX (object id 69658)
     99    INDEX RANGE SCAN ACC_IDX (object id 69660)
begin
    for x in ( select * from session_trace_file_name )
    loop
        if ( dbms_lob.fileexists( bfilename('UDUMP_DIR', x.filename ) ) = 1 )
        then
            insert into avail_trace_files (filename) values (x.filename);
        end if;
    end loop;
call     count       cpu    elapsed       disk      query    current        rows
Parse        1      0.00       0.00          0          0          0           0
Execute      1      0.01       0.00          0          0          0           1
Fetch        0      0.00       0.00          0          0          0           0
total        2      0.01       0.00          0          0          0           1
Misses in library cache during parse: 0
Optimizer goal: CHOOSE
Parsing user id: 736     (recursive depth: 1)
select *
from
session_trace_file_name
call     count       cpu    elapsed       disk      query    current        rows
Parse        1      0.00       0.00          0          0          0           0
Execute      1      0.00       0.00          0          0          0           0
Fetch        2      0.00       0.00          0          0          0           1
total        4      0.00       0.00          0          0          0           1
Misses in library cache during parse: 0
Optimizer goal: CHOOSE
Parsing user id: 736     (recursive depth: 2)
INSERT into avail_trace_files (filename)
values
(:b1)
call     count       cpu    elapsed       disk      query    current        rows
Parse        1      0.00       0.00          0          0          0           0
Execute      1      0.00       0.00          0          0          3           1
Fetch        0      0.00       0.00          0          0          0           0
total        2      0.00       0.00          0          0          3           1
Misses in library cache during parse: 0
Optimizer goal: CHOOSE
Parsing user id: 736     (recursive depth: 2)
OVERALL TOTALS FOR ALL NON-RECURSIVE STATEMENTS
call     count       cpu    elapsed       disk      query    current        rows
Parse        1      0.00       0.00          0          0          0           0
Execute      2      0.00       0.00          0          0          0           0
Fetch        1      0.11       1.81          0          1          0           0
total        4      0.11       1.81          0          1          0           0
Misses in library cache during parse: 0
OVERALL TOTALS FOR ALL RECURSIVE STATEMENTS
call     count       cpu    elapsed       disk      query    current        rows
Parse        8      0.00       0.11          0          0          0           0
Execute    409      0.02       0.04          0          0          3           2
Fetch      408      0.06       0.03          0        810          0         401
total      825      0.08       0.19          0        810          3         403
Misses in library cache during parse: 4
    9  user  SQL statements in session.
    1  internal SQL statements in session.
   10  SQL statements in session.
Trace file: ora92_ora_4092.trc
Trace file compatibility: 9.00.01
Sort options: default
       1  session in tracefile.
       9  user  SQL statements in trace file.
       1  internal SQL statements in trace file.
      10  SQL statements in trace file.
      10  unique SQL statements in trace file.
     945  lines in trace file.