Rem DML monitoring

create table mon_mods$
(
  obj#              number,                                 /* object number */
  inserts           number,  /* approx. number of inserts since last analyze */
  updates           number,  /* approx. number of updates since last analyze */
  deletes           number,  /* approx. number of deletes since last analyze */
  timestamp         date,     /* timestamp of last time this row was changed */
  flags             number,                                         /* flags */
                                           /* 0x01 object has been truncated */
  drop_segments     number   /* number of segemnt in part/subpartition table */
)
  storage (initial 200K next 100k maxextents unlimited pctincrease 0)
/
create unique index i_mon_mods$_obj on mon_mods$(obj#)
  storage (maxextents unlimited)
/

Rem DML monitoring, has info aggregated to global level for paritioned objects
create table mon_mods_all$
(
  obj#              number,                                 /* object number */
  inserts           number,  /* approx. number of inserts since last analyze */
  updates           number,  /* approx. number of updates since last analyze */
  deletes           number,  /* approx. number of deletes since last analyze */
  timestamp         date,     /* timestamp of last time this row was changed */
  flags             number,                                         /* flags */
                                           /* 0x01 object has been truncated */
  drop_segments     number   /* number of segemnt in part/subpartition table */
)
  storage (initial 200K next 100k maxextents unlimited pctincrease 0)
/
create unique index i_mon_mods_all$_obj on mon_mods_all$(obj#)
  storage (maxextents unlimited)
/

Rem =========================================================================
Rem End Usage monitoring tables
Rem =========================================================================

VIEW DBA_TAB_MODIFICATIONS

select u.name, o.name, null, null,
       m.inserts, m.updates, m.deletes, m.timestamp,
       decode(bitand(m.flags,1),1,'YES','NO'),
       m.drop_segments
from sys.mon_mods_all$ m, sys.obj$ o, sys.tab$ t, sys.user$ u
where o.obj# = m.obj# and o.obj# = t.obj# and o.owner# = u.user#
union all
select u.name, o.name, o.subname, null,
       m.inserts, m.updates, m.deletes, m.timestamp,
       decode(bitand(m.flags,1),1,'YES','NO'),
       m.drop_segments
from sys.mon_mods_all$ m, sys.obj$ o, sys.user$ u
where o.owner# = u.user# and o.obj# = m.obj# and o.type#=19
union all
select u.name, o.name, o2.subname, o.subname,
       m.inserts, m.updates, m.deletes, m.timestamp,
       decode(bitand(m.flags,1),1,'YES','NO'),
       m.drop_segments
from sys.mon_mods_all$ m, sys.obj$ o, sys.tabsubpart$ tsp, sys.obj$ o2,
     sys.user$ u
where o.obj# = m.obj# and o.owner# = u.user# and
      o.obj# = tsp.obj# and o2.obj# = tsp.pobj#

SQL> select * from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
PL/SQL Release 11.2.0.2.0 - Production
CORE    11.2.0.2.0      Production
TNS for Linux: Version 11.2.0.2.0 - Production
NLSRTL Version 11.2.0.2.0 - Production

SQL> select * from global_name;

GLOBAL_NAME
--------------------------------------------------------------------------------
www.oracledatabase12g.com

/* 填充mon_mods$字典基表 */

lock table sys.mon_mods$ in exclusive mode nowait

insert into sys.mon_mods$
  (obj#, inserts, updates, deletes, timestamp, flags, drop_segments)
values
  (:1, :2, :3, :4, :5, :6, :7)

update sys.mon_mods$
   set inserts       = inserts + :ins,
       updates       = updates + :upd,
       deletes       = deletes + :del,
       flags        =
       (decode(bitand(flags, :flag), :flag, flags, flags + :flag)),
       drop_segments = drop_segments + :dropseg,
       timestamp     = :time
 where obj# = :objn

lock table sys.mon_mods_all$ in exclusive mode

/* 以下merge命令会将mon_mods$中的记录合并到mon_mods_all$,
   若有匹配的记录，则在原记录的基础上增加inserts、updates、deletes总数，
   否则插入新的记录
*/

merge /*+ dynamic_sampling(mm 4) dynamic_sampling_est_cdn(mm)
dynamic_sampling(m 4) dynamic_sampling_est_cdn(m) */
into sys.mon_mods_all$ mm
using (select m.obj#          obj#,
              m.inserts       inserts,
              m.updates       updates,
              m.deletes       deletes,
              m.flags         flags,
              m.timestamp     timestamp,
              m.drop_segments drop_segments fr om sys.mon_mods$ m,
              tab$            t where m.obj# = t.obj#) v
on (mm.ob j# = v.obj#)
when matched then
  update
     set mm.inserts       = mm.inserts + v.inserts,
         mm.updates       = mm.updates + v.updates,
         mm.deletes       = mm.deletes + v.deletes,
         mm.flags         = mm.flags + v.flags - bitand(mm.flags, v.flags) /* bitor(mm.flags,v.flags) */,
         mm.timestamp     = v.timestamp,
         mm.drop_segments = mm.drop_segments + v.drop_segments
when NOT matched then
  insert
    (obj#, inserts, updates, deletes, timestamp, flags, drop_segments)
  values
    (v.obj#,
     v.inserts,
     v.updates,
     v.deletes,
     sysdate,
     v.flags,
     v.drop_segments) / all merge /*+ dynamic_sampling(mm 4) dynamic_sampling_est_cdn(mm)
dynamic_sampling(m 4) dynamic_sampling_est_cdn(m) */
  into sys.mon_mods_all$ mm using
    (select m.obj#          obj#,
            m.inserts       inserts,
            m.updates       updates,
            m.deletes       deletes,
            m.flags         flags,
            m.timestamp     timestamp,
            m.drop_segments drop_segments fr om sys.mon_mods$ m,
            tab$            t where m.obj# = t.obj#) v on
    (mm.ob j# = v.obj#)
when matched then
  update
     set mm.inserts       = mm.inserts + v.inserts,
         mm.updates       = mm.updates + v.updates,
         mm.deletes       = mm.deletes + v.deletes,
         mm.flags         = mm.flags + v.flags - bitand(mm.flags, v.flags)
         /* bitor(mm.flags,v.flags) */,
         mm.timestamp     = v.timestamp,
         mm.drop_segments = mm.drop_segments + v.drop_segments
when NOT matched then
  insert
    (obj#, inserts, updates, deletes, timestamp, flags, drop_segments)
  values
    (v.obj#,
     v.inserts,
     v.updates,
     v.deletes,
     sysdate,
     v.flags,
     v.drop_segments)

/* 最后删除sys.mon_mods$上的相关记录 */

delete /*+ dynamic_sampling(m 4) dynamic_sampling_est_cdn(m) */
from sys.mon_mods$ m
 where exists (select /*+ unnest */
         *
          from sys.tab$ t
         where t.obj# = m. obj#)

  select obj#
    from sys.mon_mods$
   where obj# not in (select obj# from sys.obj$)

Used to have a FULL TABLE SCAN on obj$ associated with monitoring information
extracted in conjunction with mon_mods$ executed by SMON periodically.

kglpnal <- kglpin <- kxsGetRuntimeLock
<- kksfbc <- kkspsc0 <- kksParseCursor <- opiosq0 <- opiall0
<- opikpr <- opiodr <- PGOSF175_rpidrus <- skgmstack <- rpiswu2
<- kprball <- kprbbnd0 <- kprbbnd <- ksxmfmel <- ksxmfm
<- ksxmfchk <- ksxmftim <- ktmmon <- ktmSmonMain <- ksbrdp
<- opirip <- opidrv <- sou2o <- opimai_real <- ssthrdmain
<- main <- libc_start_main <- start

SQL> select * from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
PL/SQL Release 11.2.0.2.0 - Production
CORE    11.2.0.2.0      Production
TNS for Linux: Version 11.2.0.2.0 - Production
NLSRTL Version 11.2.0.2.0 - Production

SQL> select * from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
PL/SQL Release 11.2.0.2.0 - Production
CORE    11.2.0.2.0      Production
TNS for Linux: Version 11.2.0.2.0 - Production
NLSRTL Version 11.2.0.2.0 - Production

SQL> create table maclean1 (t1 int);

Table created.

/* 在10g以后nomonitoring或monitoring选项不再有效  */

SQL> create table maclean2 (t1 int) nomonitoring;

Table created.

SQL>  select table_name,monitoring from dba_tables  where table_name like 'MACLEAN%';


TABLE_NAME                     MON
------------------------------ ---
MACLEAN1                       YES
MACLEAN2                       YES

show parameter statistics_level
alter system set statistics_level = basic;

 #diable 11g AMM ,have to bounce instance
 #alter system set memory_target =0 scope=spfile;
 #diable 10g ASMM
 alter system set sga_target=0;
 alter system set statistics_level = basic;

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