Developers will often want to get some idea of the system statistics due to their activity, and for a long time the standard method for doing this is to look at the dynamic perfomance view V$SESSTAT - session statistics, joining it to the view V$STATNAME - statistics names.
The V$SESSTAT view, however, is super-imposed on X$KSUSESTA, a rather large object in the SGA which holds statistics about ALL user sessions, both active and potential, the overhead of using this object too casually can be quite significant.
Since Oracle 7.3, there has been a more efficient object - X$KSUMYSTA, which is part of the UGA, and contains only the statistics for the current user session. This object has remarkably low visibility in Oracle, even to the extent that the AUTOTRACE facility uses v$sesstat rather than v$mystat.
As a minor convenience to developers, therefore, I tend to create a view to make v$mystat more visible, and more easliy usable, with the following script which has to be run under the SYS account.
rem rem Script: my_stat.sql rem Author: J.P.Lewis rem Dated: 12-Sep-1999 rem Purpose: Naming the 'per-session' statistics. rem rem Use: rem ---- rem This script should be run as SYS create or replace view v$my_stats as select sn.name, ms.value from v$mystat ms, v$statname sn where ms.statistic# = sn.statistic# ; drop public synonym v$my_stats; create public synonym v$my_stats for v$my_stats; grant select on v$my_stats to public;