Clever bulk collect working with 9.2 and up for snaps .

Question

Hi,
I'm doing snaps of v$sysstat with 1 second delay to count some metrics like that:
select name,value from v$sysstat
where
name in ('execute count', 'parse count (hard)', 'parse count (total)',
                          'physical read total IO requests', 'physical read total bytes',
                          'physical write total IO requests', 'physical write total bytes',
                          'redo size', 'redo writes', 'session cursor cache hits',
                          'session logical reads', 'user calls', 'user commits') ;
dbms_lock.sleep(1);
select name,value from v$sysstat
where
name in ('execute count', 'parse count (hard)', 'parse count (total)',
                          'physical read total IO requests', 'physical read total bytes',
                          'physical write total IO requests', 'physical write total bytes',
                          'redo size', 'redo writes', 'session cursor cache hits',
                          'session logical reads', 'user calls', 'user commits') ;But Im really interest in deltas so think, maybe bulk collect into is the obvious solution .
I can workaround that with doing pivot and self join to get only 1 row per query , and then just do the math .
Wondering how to construct collection to support my query ?
Code should be working on 9.2 and above .
Regards
GregG

Answer 1

Something like this:
SQL> set lines 120 pages 999
SQL> col name for a50
SQL> var r refcursor
SQL> set autoprint on
SQL> declare
  2   beg_stats_type_tt stats_type_tt := stats_type_tt();
  3   end_stats_type_tt stats_type_tt := stats_type_tt();
  4   srt_stats_type_tt stats_type_tt := stats_type_tt();
  5  begin
  6  select stats_type(name, value) bulk collect into beg_stats_type_tt
  7  from v$sysstat
  8  where
  9  name in ('execute count', 'parse count (hard)', 'parse count (total)',
10                            'physical read total IO requests', 'physical read total bytes',
11                            'physical write total IO requests', 'physical write total bytes',
12                            'redo size', 'redo writes', 'session cursor cache hits',
13                            'session logical reads', 'user calls', 'user commits');
14  dbms_lock.sleep(1);
15  select stats_type(name, value) bulk collect into end_stats_type_tt
16  from v$sysstat
17  where
18  name in ('execute count', 'parse count (hard)', 'parse count (total)',
19                            'physical read total IO requests', 'physical read total bytes',
20                            'physical write total IO requests', 'physical write total bytes',
21                            'redo size', 'redo writes', 'session cursor cache hits',
22                            'session logical reads', 'user calls', 'user commits');
23  open :r for
24  select b.name, e.value - b.value
25  from   table(cast(beg_stats_type_tt as stats_type_tt)) b
26  ,      table(cast(end_stats_type_tt as stats_type_tt)) e
27  where  e.name = b.name;
28  end;
29  /
PL/SQL procedure successfully completed.
NAME                                               E.VALUE-B.VALUE
user commits                                                     0
user calls                                                      39
session logical reads                                            0
physical read total IO requests                                  0
physical read total bytes                                        0
physical write total IO requests                                 0
physical write total bytes                                       0
redo size                                                        0
redo writes                                                      0
session cursor cache hits                                        1
parse count (total)                                              0
parse count (hard)                                               0
execute count                                                    3
13 rows selected.
SQL>Pipelined table function another option - then you can just issue a select.
That will require permanent object types as well though (for 9.2. compatibility at least).
Edited by: Dom Brooks on May 22, 2012 11:10 AM