一、select a.snap_id,
a.dbid,
a.instance_number,
db_time,
to_char(trunc((db_time - lag(db_time, 1, db_time)
over(partition by stat_name,
instance_number order by snap_id)) / 1000000 / 60,
2)) db_time_
from (select a.snap_id,
a.dbid,
a.instance_number,
a.stat_name,
sum(a.value) db_time
from dba_hist_sys_time_model a
where a.stat_name = 'db time'
--and a.instance_number = 2
group by a.snap_id, a.dbid, a.instance_number, a.stat_name) a;
select a.snap_id,
a.dbid,
a.instance_number,
db_time,
/* to_char(trunc((db_time - lag(db_time, 1, db_time)
over(partition by stat_name,
instance_number order by snap_id)) / 1000000 / 60,
2)) db_time_, */
b.end_interval_time
from (select a.snap_id,
a.dbid,
a.instance_number,
a.stat_name,
sum(a.value) db_time
from dba_hist_sys_time_model a
where a.stat_name = 'db time'
group by a.snap_id, a.dbid, a.instance_number, a.stat_name) a,dba_hist_snapshot b where a.snap_id=b.snap_id;
執行上面兩個語句得到資料之後按照snap_id對應起來，可以得到snap_id、db_time_、end_interval_time這仨個字段，就可以確定某個時間點的db_time值與snap_id所對應的具體的時間。
然後把相應時間段的snap_id代入下面的語句即可得到top10的語句
select to_char(t.instance_number) i_n,t.sql_id,to_char(t.username) username,
to_char(t.disk_reads) d_r,to_char(t.buffer_gets_nvl) buffer_nvl,t.bget buffer_gets,t.elap_time,t.cpu_time,
t.exec,t.elap_nvl,t.sql_text
from
(select sqt.bget,
sqt.exec,
username,
instance_number,
disk_reads,
decode(sqt.exec, 0, to_number(null) , (sqt.bget / sqt.exec)) buffer_gets_nvl,
nvl((sqt.cput / 1000000), to_number(null)) cpu_time ,
nvl((sqt.elap / 1000000), to_number(null)) elap_time,
(sqt.elap / 1000000) / sqt.exec elap_nvl,
sqt.sql_id,
st.sql_text
from
(select sql_id,parsing_schema_name username,instance_number,
sum(buffer_gets_delta) bget,
sum(executions_delta) exec,
sum(cpu_time_delta) cput,
sum(elapsed_time_delta) elap,
sum(disk_reads_delta) disk_reads
from dba_hist_sqlstat
where snap_id>=30281 and snap_id<=30307 ---------------把相關時間點的snap_id寫到這裡即可
group by sql_id,parsing_schema_name,instance_number) sqt,
dba_hist_sqltext st
where st.sql_id(+) = sqt.sql_id
and sqt.exec != 0
and st.sql_text not like '%dual%%'
order by nvl((sqt.cput / 1000000), to_number(null)) desc, sqt.sql_id ,username,instance_number,disk_reads) t
where rownum < 65
and (rownum <= 10);
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