Oracle 9 bug (all platforms affected)

Question

Don't have paid support so I don't know where else I can report this bug.
Oracle 9 - all platforms (used to work in Oracle 8).
create table test (k raw(10) primary key, v varchar(10))
create index x on test(k) descending
insert some data
The following select statement will work incorrectly:
select --+ INDEX_ASC(test)
* from test where k > some_value and rownum = 1 order by k
It might work ok if you don't put the hint.
It will work also if you don't have ANY other indexes on that table.
Regards,
Sergey

Answer 1

How big are these tables? I did some tests on a table with around 35,000 rows (I know not big) and the result was returned in 0.2 or 0.4 of a second? Does it need to be faster. How many rows and what response times are you seeing?
SQL> create table t (
  2    k raw(20), v varchar2(30),
  3    constraint test_pk  primary key (k)
  4    )
  5  /
Table created.
SQL> insert into t select utl_raw.cast_from_number(object_id), object_name from all_objects;
36297 rows created.
SQL> exec dbms_stats.gather_table_stats(user, 't', cascade => true)
PL/SQL procedure successfully completed.
SQL> set autotrace on
SQL> select min(k) from t
  2  where k > utl_raw.cast_from_number(10000);
MIN(K)
C302015D
Execution Plan
   0      SELECT STATEMENT Optimizer=CHOOSE (Cost=1 Card=1 Bytes=5)
   1    0   SORT (AGGREGATE)
   2    1     FIRST ROW (Cost=2 Card=1815 Bytes=9075)
   3    2       INDEX (RANGE SCAN (MIN/MAX)) OF 'TEST_PK' (UNIQUE) (Cost=2 Card=20)
Statistics
          0  recursive calls
          0  db block gets
          2  consistent gets
          0  physical reads
          0  redo size
        210  bytes sent via SQL*Net to client
        248  bytes received via SQL*Net from client
          2  SQL*Net roundtrips to/from client
          0  sorts (memory)
          0  sorts (disk)
          1  rows processed
SQL> edi
Wrote file afiedt.sql
  1  select t.* from t,
  2  (select min(k) x from t
  3    where k > utl_raw.cast_from_number(10000))
  4* where k = x
SQL> /
K                                        V
C302015D                                 EXC_FFRPRFUP
Execution Plan
   0      SELECT STATEMENT Optimizer=CHOOSE (Cost=2 Card=1 Bytes=39)
   1    0   NESTED LOOPS (Cost=2 Card=1 Bytes=39)
   2    1     VIEW (Cost=1 Card=1 Bytes=12)
   3    2       SORT (AGGREGATE)
   4    3         FIRST ROW (Cost=2 Card=1815 Bytes=9075)
   5    4           INDEX (RANGE SCAN (MIN/MAX)) OF 'TEST_PK' (UNIQUE) (Cost=2 Card=20)
   6    1     TABLE ACCESS (BY INDEX ROWID) OF 'T' (Cost=1 Card=1 Bytes=27)
   7    6       INDEX (UNIQUE SCAN) OF 'TEST_PK' (UNIQUE)
Statistics
          5  recursive calls
          0  db block gets
          7  consistent gets
          0  physical reads
          0  redo size
        243  bytes sent via SQL*Net to client
        248  bytes received via SQL*Net from client
          2  SQL*Net roundtrips to/from client
          2  sorts (memory)
          0  sorts (disk)
          1  rows processed
SQL> set autotrace off
SQL> select t.* from t,
  2  (select min(k) x from t
  3    where k > utl_raw.cast_from_number(10000))
  4  where k = x
  5  /
K                                        V
C302015D                                 EXC_FFRPRFUP
SQL> set timing on
SQL> /
K                                        V
C302015D                                 EXC_FFRPRFUP
Elapsed: 00:00:00.20
SQL> edi
Wrote file afiedt.sql
  1  select t.* from t,
  2  (select min(k) x from t
  3    where k > utl_raw.cast_from_number(15000))
  4* where k = x
SQL> /
K                                        V
C3023303                                 AA_COL
Elapsed: 00:00:00.30
SQL> edi
Wrote file afiedt.sql
  1  select * from t
  2  where k = (select min(k) x from t
  3*   where k > utl_raw.cast_from_number(17000))
SQL> /
K                                        V
C3024705                                 EXC_FFRFSFND
Elapsed: 00:00:00.40
SQL>This
select --+ INDEX_ASC(tablename tablename)
... etc ...is still a lucky accident and is not guaranteed to always give you the correct answer.