A handy little script that I have used in the Oracle Database 11g Performance Tuning course this week. It queries the AWR Snapshots for SQL statements and sorts them by elapsed time:

SQL> col parsed format a6
col sql_text format a40
set lines 200
set pages 300

select     
 sql_text,
 parsing_schema_name as parsed,
 elapsed_time_delta/1000/1000 as elapsed_sec,
 stat.snap_id,
 to_char(snap.end_interval_time,'dd.mm hh24:mi:ss') as snaptime,
 txt.sql_id
from     
 dba_hist_sqlstat stat,
 dba_hist_sqltext txt,
 dba_hist_snapshot snap
where     
 stat.sql_id=txt.sql_id and
 stat.snap_id=snap.snap_id and
 snap.begin_interval_time>=sysdate-1 and
 lower(sql_text) like '%&t%' and
 parsing_schema_name not in ('SYS','SYSMAN','MDSYS','WKSYS')
order by elapsed_time_delta asc;

sysdate-1 returns SQL up to yesterday and can be modified to retrieve SQL as long as there are AWR snapshots of course. &t is a substring of the SQL, we may be interested in. With the sql_id, we can also retrieve the execution plan from the snapshots:

SQL> select plan_table_output from table (dbms_xplan.display_awr('&sqlid'));

The amount of SQL that gets collected into a snapshot can be modified with

SQL> begin
dbms_workload_repository.modify_snapshot_settings (
 topnsql=>'MAXIMUM');
end;
/

MAXIMUM (uppercase!) takes all SQL from the Library Cache into the snapshot – alternative, we can specify a number of Top SQL to collect. The example is from an 11g Database, but it should work the same with 10g already.