定期自动统计大表执行情况

一、创建用户并赋权

sql 复制代码

create user dbtj identified by oracle default tablespace OGGTBS;

grant connect,resource to dbtj;

grant select any dictionary to dbtj;

grant create job to dbtj;

grant manage scheduler to dbtj;

二、创建存储表

1、连接到新建用户

conn dbtj/oracle

2、按大表2千万为维度，统计出大表，再根据大表找到最近一天的sql，统计其执行效率（毫秒），创建数据存储表

sql 复制代码

create table dbtj.dbtj_tab as

select to_char(b.end_interval_time, 'yyyy-mm-dd-hh24') as datet,

SQL_ID,

sum(a.executions_delta) exec_d,

sum(a.buffer_gets_delta) buffer_d,

sum(a.disk_reads_delta) disk_d,

round(sum(a.elapsed_time_delta / 1000000), 3) et_d,

round(decode(sum(a.executions_delta),

0,

sum(a.elapsed_time_delta),

sum(a.elapsed_time_delta / 1000) /

sum(a.executions_delta)),

2) et_onetime

from dba_hist_sqlstat a, dba_hist_snapshot b

where a.snap_id = b.snap_id

and a.instance_number = b.instance_number

and a.sql_id IN

(SELECT DISTINCT (SQL_ID)

FROM GV$SQL_PLAN SP

WHERE (sp.OBJECT_OWNER, sp.OBJECT_NAME) in

(select owner, table_name

from dba_tables

where num_rows >= 20000000

and owner not in ('SYS', 'SYSTEM')))

AND B.end_interval_time >= SYSDATE - 6/24

group by to_char(b.end_interval_time, 'yyyy-mm-dd-hh24'), SQL_ID

having(sum(a.executions_delta)) > 0

order by 1;

三、创建存储过程，将第二步的查询结果插入到数据表dbtj_tab

sql 复制代码

create or replace procedure dbtj_proc

as

begin

insert into dbtj.dbtj_tab

select to_char(b.end_interval_time, 'yyyy-mm-dd-hh24') as datet,

SQL_ID,

sum(a.executions_delta) exec_d,

sum(a.buffer_gets_delta) buffer_d,

sum(a.disk_reads_delta) disk_d,

round(sum(a.elapsed_time_delta / 1000000), 3) et_d,

round(decode(sum(a.executions_delta),

0,

sum(a.elapsed_time_delta),

sum(a.elapsed_time_delta / 1000) /

sum(a.executions_delta)),

2) et_onetime

from dba_hist_sqlstat a, dba_hist_snapshot b

where a.snap_id = b.snap_id

and a.instance_number = b.instance_number

and a.sql_id IN

(SELECT DISTINCT (SQL_ID)

FROM GV$SQL_PLAN SP

WHERE (sp.OBJECT_OWNER, sp.OBJECT_NAME) in

(select owner, table_name

from dba_tables

where num_rows >= 20000000

and owner not in ('SYS', 'SYSTEM')))

AND B.end_interval_time >= SYSDATE - 6/24

group by to_char(b.end_interval_time, 'yyyy-mm-dd-hh24'), SQL_ID

having(sum(a.executions_delta)) > 0

order by 1;

commit;

end;

四、创建定时任务，每天1、7、13、19 统计

sql 复制代码

begin

dbms_scheduler.create_job(

job_name =>'dbtj_job',

job_type =>'STORED_PROCEDURE',

JOB_ACTION =>'dbtj_proc',

START_DATE =>TO_TIMESTAMP_TZ('2022-07-11 22:10:00 +8:00','YYYY-MM-DD HH24:MI:SS TZH:TZM'),

REPEAT_INTERVAL =>'FREQ=DAILY;BYHOUR=01,07,13,19',

ENABLED =>TRUE);

END;

五、测试

sql 复制代码

begin

dbtj_proc;

end;


begin

dbms_scheduler.enable('dbtj_job');

end;


begin

dbms_scheduler.run_job('dbtj_job');

end;


BEGIN

DBMS_SCHEDULER.DROP_JOB('dbtj_job');

END;


select * from dbtj.dbtj_tab;

六、结果展示

sql 复制代码

dbtj.dbtj_tab

select datet as "时间",sql_id,exec_d as "执行次数",et_onetime as "每次耗时（毫秒）" from dbtj.dbtj_tab where datet >= to_char(sysdate-1,'yyyy-mm-dd-hh24') order by 1;