分享一个oracle数据库巡检脚本,欢迎大家使用,希望大家在用的过程中发现脚本中的错误并提出改进意见。
Rem 数据库巡检脚本
Rem 更新时间于2020-4-15,版本号2.2
Rem 该脚本仅对数据库的做一个初步的巡检,具体的优化方案应结合监控、awr、ash去具体分析 Rem 设置相关格式
set feedback off verify off trimspool on term off timing off heading on
set pagesize 100 linesize 500 Rem 生成的文件 ~/oracle_xj_实例名_日期.txt
column inst_name new_value inst_name noprint
select instance_name inst_name from v$instance;
column txt_time new_value txt_time noprint
select to_char(sysdate,'yyyymmdd') txt_time from dual;
spool /home/oracle/oracle_xj_&inst_name._&txt_time..txt prompt 说明:如果有的条目没有结果,则该条目状态正常
prompt
prompt 一、数据库的基本情况
prompt
prompt 1.1、数据库基本信息
col host_name for a20
select dbid, name db_name, instance_name, version, parallel rac, host_name
from v$database, v$instance; prompt
prompt 1.2、实例状态
select instance_number, instance_name, status, host_name from gv$instance; prompt
prompt 1.3、数据库运行时间
col run_time for a28
select instance_number,
to_char(startup_time, 'yyyy-mm-dd hh24:mi:ss') startup_time,
trunc(sysdate - (startup_time)) || 'day '
|| trunc(24 * ((sysdate - startup_time) - trunc(sysdate - startup_time))) || 'hour '
|| mod(trunc(1440 * ((sysdate - startup_time) - trunc(sysdate - startup_time))), 60) || 'min '
|| mod(trunc(86400 * ((sysdate - startup_time) - trunc(sysdate - startup_time))), 60) || 'min' run_time
from gv$instance; prompt
prompt 二、数据库的cpu、内存情况
prompt
prompt 2.1、cpu情况
col stat_name for a20
col percent for a10
select stat_name,
to_char((value * 100 / (sum(value) over())), 90.99) || '%' percent
from v$osstat
where stat_name in
('IDLE_TIME', 'BUSY_TIME', 'USER_TIME', 'SYS_TIME', 'IOWAIT_TIME'); prompt
prompt 2.2、sga及其组件大小
prompt 参考值: Buffer_cache_size:70%sga,Shared_pool_size:15%sga左右
col name for a35
col percent for a10
with tmp as
(select decode(a.value, 0, b.value, null, b.value, a.value) sga_size
from (select name, value from v$parameter where name = 'sga_target') a,
(select name, value from v$parameter where name = 'sga_max_size') b)
select name,
round(bytes / 1024 / 1024) size_mb, round(sga_size / 1024 / 1024) sga_mb,
round(100 * bytes / sga_size, 2) || '%' percent
from v$sgainfo, tmp
where name in ('Buffer Cache Size', 'Shared Pool Size'); prompt
prompt 2.3、pga大小
prompt 参考值:pga大小为30%sga左右
col name for a30
select name, round(value / 1024 / 1024) size_mb
from v$parameter
where name = 'pga_aggregate_target'; prompt
prompt 三、检查各文件状态
prompt
prompt 3.1、查看参数文件
col name for a20
col value for a40
select name, value from v$parameter where name = 'spfile'; prompt
prompt 3.2、查看控制文件
col name for a60
select name, status from v$controlfile; prompt
prompt 3.3、查看在线日志
col member for a50
select a.group#,
a.status,
a.type,
a.member,
(b.bytes / 1024 / 1024) onl_size_mb,
(c.bytes / 1024 / 1024) std_size_mb
from v$logfile a, v$log b, v$standby_log c
where a.group# = b.group#(+)
and a.group# = c.group#(+)
order by 3, 1; prompt
prompt 3.4、检查最近一天日志切换频率
select thread#,
sequence#,
to_char(first_time, 'yyyy-mm-dd hh24:mi:ss') first_time,
case
when minutes < 0 then
null
else
minutes
end mitutes
from (select thread#,
sequence#,
first_time,
round((first_time - lag(first_time) over(order by thread#, first_time)) * 24 * 60, 2) minutes
from v$log_history
where first_time > sysdate - 2)
where first_time > sysdate - 1
order by thread#, first_time; prompt
prompt 3.4.1、检查最近一周日志切换
select to_char(first_time, 'yyyy.mm.dd') day,
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "00",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "01",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "02",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "03",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "04",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "05",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "06",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "07",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "08",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "09",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "10",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "11",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "12",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "13",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "14",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "15",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "16",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "17",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "18",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "19",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "20",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "21",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "22",
to_char(sum(decode(to_char(first_time,'hh24'),'',1,0)),'') "23"
from v$log_history where first_time > trunc(sysdate) - 7
group by to_char(first_time, 'yyyy.mm.dd') order by 1 desc; prompt
prompt 3.5、查看asm磁盘组空间
col name for a20
col used_percent for 9999
select group_number,
name,
type,
total_mb,
usable_file_mb,
round(100 - usable_file_mb * decode(type, 'EXTERN', 1, 'NORMAL', 3, 'HIGH', 5) * 100 / (total_mb)) used_percent
from v$asm_diskgroup; prompt
prompt 3.6、查看表空间的使用情况
select tablespace_name,
round(used / 1024 / 1024) used_mb,
round(total / 1024 / 1024) total_mb,
to_char(round(used / total * 100, 2), '9999990.99') used_percent
from (select a.tablespace_name,
(a.bytes_alloc - b.bytes_free) used,
a.bytes_total total
from (select tablespace_name,
sum(bytes) bytes_alloc,
sum(greatest(bytes, maxbytes)) bytes_total
from dba_data_files
group by tablespace_name) a,
(select tablespace_name, sum(bytes) bytes_free
from dba_free_space
group by tablespace_name) b
where a.tablespace_name = b.tablespace_name)
order by 4; prompt
prompt 3.7、查看临时表空间使用情况
select tablespace_name,
used used_mb,
allocate allocate_mb,
total total_mb,
to_char(round(used / total * 100, 2), '990.99') used_percent
from (select tablespace_name,
(select sum(blocks) / 128 from v$tempseg_usage) used,
round(sum(bytes) / 1024 / 1024) allocate,
round(sum(greatest(bytes, maxbytes)) / 1024 / 1024) total
from dba_temp_files
group by tablespace_name); prompt
prompt 3.8、查看临时段使用的情况
col username for a20
col segtype for a10
select username,
segtype,
extents extents_allocated,
blocks blocks_allocated
from v$tempseg_usage
order by 1, 2; prompt
prompt 3.9、查看数据文件状态
col name for a30
select b.name tablespace_name, a.status, count(*)
from v$datafile a, v$tablespace b
where a.ts# = b.ts#
group by b.name, a.status
order by 1; prompt
prompt 3.10、归档日志检查
col dest_name for a20
col error for a40
col gap_status for a10
select dest_id, dest_name, status, type, error, gap_status
from v$archive_dest_status
where status <> 'INACTIVE'; prompt
prompt 3.11、最近一周备份情况
select input_type, output_device_type, start_time, status
from v$rman_backup_job_details
where start_time > sysdate - 7
order by start_time desc; prompt
prompt 四、检查数据库对象状态
prompt
prompt 4.1、查看回滚段状态
select status, count(*) from dba_rollback_segs group by status; prompt
prompt 4.2、检查是否有禁用约束
col owner for a20
select owner, constraint_name, table_name, constraint_type, status
from dba_constraints
where status = 'DISABLED'
and owner not in ('SYS',
'SYSTEM',
'WMSYS',
'DBSNMP',
'XDB',
'EXFSYS',
'CTXSYS',
'MDSYS',
'OLAPSYS',
'SYSMAN',
'APEX_030200',
'OUTLN',
'ORDDATA',
'ORDSYS',
'RMAN')
order by 1, 3; prompt
prompt 4.3、检查是否有禁用触发器
col owner for a20
col taigger_name for a10
col table_name for a30
col table_name for a30
select owner, trigger_name, table_name, status
from dba_triggers
where status = 'DISABLED'
and owner not in ('SYS',
'SYSTEM',
'WMSYS',
'DBSNMP',
'XDB',
'EXFSYS',
'CTXSYS',
'MDSYS',
'OLAPSYS',
'SYSMAN',
'APEX_030200',
'OUTLN',
'ORDDATA',
'ORDSYS',
'RMAN')
order by 1, 3; prompt
prompt 4.4、oracle job是否有失败
col what for a50
select job, what, last_date, next_date, failures, broken
from dba_jobs
where failures > 0
or broken = 'Y'; prompt
prompt 4.5、查看无效的对象
col object_name for a40
select owner, object_name, object_type, last_ddl_time
from dba_objects
where status != 'VALID'
and owner not in ('SYS',
'SYSTEM',
'WMSYS',
'DBSNMP',
'XDB',
'EXFSYS',
'CTXSYS',
'MDSYS',
'OLAPSYS',
'SYSMAN',
'APEX_030200',
'OUTLN',
'ORDDATA',
'ORDSYS',
'RMAN',
'PUBLIC')
order by 1, 3; prompt
prompt 4.6、检查失效的索引
select owner, index_name, table_name, tablespace_name, status
from dba_indexes
where status not in ('VALID', 'N/A')
order by 1, 3; prompt
prompt 4.7、并行度大于1的索引
col owner for a25
col table_name for a30
col index_name for a30
col degree for a10
select owner, table_name, index_name, degree
from dba_indexes
where degree > ''
order by 1, 2; prompt
prompt 4.8、索引冗余
col owner for a25
col table_name for a30
col redundant_index for a30
col sufficient_index for a30
select o1.name owner,
x.table_name,
n1.name redundant_index,
n2.name sufficient_index
from sys.icol$ ic1,
sys.icol$ ic2,
sys.ind$ i1,
sys.obj$ n1,
sys.obj$ n2,
sys.user$ o1,
sys.user$ o2,
dba_indexes x
where ic1.pos# = 1
and ic2.bo# = ic1.bo#
and ic2.obj# != ic1.obj#
and ic2.pos# = 1
and ic2.intcol# = ic1.intcol#
and i1.obj# = ic1.obj#
and bitand(i1.property, 1) = 0
and (select max(pos#) * (max(pos#) + 1) / 2
from sys.icol$
where obj# = ic1.obj#) =
(select sum(xc1.pos#)
from sys.icol$ xc1, sys.icol$ xc2
where xc1.obj# = ic1.obj#
and xc2.obj# = ic2.obj#
and xc1.pos# = xc2.pos#
and xc1.intcol# = xc2.intcol#)
and n1.obj# = ic1.obj#
and n2.obj# = ic2.obj#
and o1.user# = n1.owner#
and o2.user# = n2.owner#
and x.index_name = n1.name
and n1.name not like 'BIN$%'
and o1.name not in ('SYS',
'SYSTEM',
'WMSYS',
'DBSNMP',
'XDB',
'EXFSYS',
'CTXSYS',
'MDSYS',
'OLAPSYS',
'SYSMAN',
'APEX_030200',
'OUTLN',
'ORDDATA',
'ORDSYS',
'RMAN')
order by 1, 2; prompt
prompt 4.9、检查碎片程度高的表
prompt 找出总大小超过1G,且使用率不足70%的表
col used_percent for a15
select owner,
table_name,
used used_mb,
total total_mb,
round(used * 100 / total) || '%' used_percent,
num_rows,
last_analyzed
from (select owner,
table_name,
round(blocks * 8192 / 1024 / 1024) total,
round(num_rows * avg_row_len / 1024 / 1024) used,
num_rows,
last_analyzed
from dba_tables)
where total > 1000
and round(used * 100 / total) < 70
order by 1, 2; prompt
prompt 4.10、检查一些扩展异常的对象
prompt 对象的extent数量超过临界值的80%,需要move
select segment_name,
segment_type,
tablespace_name,
(extents / max_extents) * 100 percent
from sys.dba_segments
where max_extents != 0
and (extents / max_extents) >= 0.8
order by percent; prompt
prompt 4.11、检查对象的下一扩展与表空间的最大扩展值
prompt 表空间的剩余空间已经无法满足对象的下次扩展,需要扩表空间
select a.table_name, a.next_extent, a.tablespace_name
from all_tables a,
(select tablespace_name, max(bytes) as big_chunk
from dba_free_space
group by tablespace_name) f
where f.tablespace_name = a.tablespace_name
and a.next_extent > f.big_chunk
union
select a.index_name, a.next_extent, a.tablespace_name
from all_indexes a,
(select tablespace_name, max(bytes) as big_chunk
from dba_free_space
group by tablespace_name) f
where f.tablespace_name = a.tablespace_name
and a.next_extent > f.big_chunk; prompt
prompt 4.12、查看行迁移或行链接
col percentage for a15
select 'chained rows' ratio,
round((select value
from v$sysstat
where name = 'table fetch continued row') /
(select value
from v$sysstat
where name = 'table scan rows gotten') * 100,
2) || '%' percentage
from dual; prompt
prompt 4.13、检查system表空间内的内容
select owner, table_name object_name, type
from (select owner, table_name, 'table' as type
from dba_tables
where tablespace_name = 'SYSTEM'
and owner != 'SYS'
and owner not in ('SYS',
'SYSTEM',
'WMSYS',
'DBSNMP',
'XDB',
'EXFSYS',
'CTXSYS',
'MDSYS',
'OLAPSYS',
'SYSMAN',
'APEX_030200',
'OUTLN',
'ORDDATA',
'ORDSYS')
union
select owner, index_name, 'index' as type
from dba_indexes
where tablespace_name = 'SYSTEM'
and owner != 'SYS'
and owner not in ('SYS',
'SYSTEM',
'WMSYS',
'DBSNMP',
'XDB',
'EXFSYS',
'CTXSYS',
'MDSYS',
'OLAPSYS',
'SYSMAN',
'APEX_030200',
'OUTLN',
'ORDDATA',
'ORDSYS'))
order by 1, 3; prompt
prompt 五、dbtime和连接情况
prompt
prompt 5.1、查看当前实例最近一天的db_time
select c.snap_id,
to_char(b.begin_interval_time, 'yyyy-mm-dd hh24:mi') begin_snapshot_time,
c.db_time
from (select a.snap_id,
trunc((db_time_1 - lag(db_time_1, 1, db_time_1)
over(partition by stat_name,
instance_number order by snap_id)) / 1000000 / 60) db_time
from (select a.snap_id,
a.dbid,
a.instance_number,
a.stat_name,
sum(a.value) db_time_1
from dba_hist_sys_time_model a
where a.stat_name = 'DB time'
and a.instance_number =
(select instance_number from v$instance)
group by a.snap_id, a.dbid, a.instance_number, a.stat_name) a) c,
dba_hist_snapshot b
where b.instance_number = (select instance_number from v$instance)
and c.snap_id = b.snap_id
and b.begin_interval_time > sysdate - 1
order by 1; prompt
prompt 5.2、检查数据库连接情况
col machine for a30
select username, program, machine, count(*)
from v$session
where username is not null
group by username, program, machine
order by 1, 4 desc; prompt
prompt 5.3、检查oracle初始化文件中相关参数值
prompt initial_allocation:软限制,limit_value:硬限制
prompt 若limit_value - max_utilization <= 5,则表明与resource_name相关的oracle初始化参数需要调整。可以通过参数文件调整。
select resource_name, max_utilization, initial_allocation, limit_value
from v$resource_limit
order by 4, 3; prompt
prompt 六、检查数据库event和sql
prompt
prompt 6.1、当前数据库的等待事件
col wait_class for a15
col event for a30
select inst_id, wait_class, event, count(*)
from gv$session
where wait_class <> 'Idle'
group by inst_id, wait_class, event
order by inst_id, wait_class, event; prompt
prompt 6.2、top5 event
prompt total_waits:总等待的次数,average_wait:每次等待的时间(ms)
col event for a30
select *
from (select event, total_waits, 10 * average_wait average_wait, wait_class#
from v$system_event
where event not like 'SQL%'
and wait_class# <> 6
order by total_waits desc)
where rownum <= 5; prompt
prompt 6.3、top10 物理读sql
col sql_text for a65
select *
from (select sql_id,
replace(substr(sql_text, 1, 300), chr(13), '') sql_text,
disk_reads,
executions,
round(disk_reads / executions) "DISKREADS/EXEC"
from v$sqlarea
where disk_reads > 0
and executions > 0
order by disk_reads desc)
where rownum <= 10; prompt
prompt 6.4、top10 逻辑读sql
select *
from (select sql_id,
replace(substr(sql_text, 1, 300), chr(13), '') sql_text,
buffer_gets,
executions,
round(buffer_gets / executions) "GETS/EXEC"
from v$sqlarea
where buffer_gets > 0
and executions > 0
order by buffer_gets desc)
where rownum <= 10; prompt
prompt 6.5、top10 物理读object
col value for 999999999999
col object_name for a30
select *
from (select owner, object_name, value
from v$segment_statistics
where statistic_name = 'physical reads'
order by value desc)
where rownum <= 10; prompt
prompt 6.6、top10 热segment
col object_name for a30
col owner for a20
select *
from (select ob.owner, ob.object_name, ob.object_type, sum(b.tch) touchs
from x$bh b, dba_objects ob
where b.obj = ob.data_object_id
and b.ts# > 0
group by ob.owner, ob.object_name, ob.object_type
order by sum(tch) desc)
where rownum <= 10; prompt
prompt 6.7、查看热点数据文件(从单块读取时间判断)
prompt cs:单块读的时间(ms),readtim:总的读时间(ms),writetim:总的写时间(ms)
col file_name for a60
select *
from (select t.file_name,
t.tablespace_name,
round(s.singleblkrdtim / s.singleblkrds / 10, 3) as cs,
round(s.readtim / 10) readtim,
round(s.writetim / 10) writetim
from v$filestat s, dba_data_files t
where s.file# = t.file_id
order by cs desc)
where rownum <= 10; prompt
prompt 6.8、检查运行很久的sql
col username for a12
col opname for a16
col progress for a8
select b.username,
a.sql_text,
b.sid,
b.serial#,
b.sofar,
b.totalwork,
round(b.sofar / b.totalwork * 100, 2) "COMPLETE%"
from gv$sql a, gv$session_longops b
where a.sql_id = b.sql_id
and a.inst_id = b.inst_id
and b.totalwork <> 0
and b.sofar <> b.totalwork; Rem 执行次数大于100次,且在一周之内发生执行计划突变的sql
prompt
prompt 6.9、检查执行计划最近一周发生突变的sql
with a as
(select sql.sql_id,
sql.plan_hash_value,
min(to_char(s.begin_interval_time, 'yyyymmdd_hh24mi')) date_time,
sum(sql.executions_delta) executions_delta,
round(avg(sql.buffer_gets_delta /
decode(nvl(sql.executions_delta, 0),
0,
1,
sql.executions_delta))) avg_lio,
round(avg((sql.cpu_time_delta / 1000000) /
decode(nvl(sql.executions_delta, 0),
0,
1,
sql.executions_delta)),
2) avg_cputime_s,
round(avg((sql.elapsed_time_delta / 1000000) /
decode(nvl(sql.executions_delta, 0),
0,
1,
sql.executions_delta)),
2) avg_etime_s,
'HIS' as status
from dba_hist_sqlstat sql, dba_hist_sql_plan spl, dba_hist_snapshot s
where sql.dbid = (select dbid from v$database)
and sql.sql_id = spl.sql_id
and spl.object_owner not in ('SYS', 'SYSTEM', 'SYSMAN')
and s.snap_id = sql.snap_id
and s.begin_interval_time between trunc(sysdate - 7) and trunc(sysdate)
and sql.executions_delta > 100
and sql.plan_hash_value <> 0
group by sql.sql_id, sql.plan_hash_value
union all
select b.sql_id,
b.plan_hash_value,
to_char(b.last_active_time, 'yyyymmdd_hh24mi'),
b.executions,
b.buffer_gets / b.executions,
b.cpu_time / 1000000 / b.executions,
b.elapsed_time / 1000000 / b.executions,
'NOW'
from v$sqlstats b
where b.executions > 100)
select sql_id, plan_hash_value, date_time, executions_delta, round(avg_lio) avg_lio, trunc(avg_cputime_s, 3) avg_cputime_s, trunc(avg_etime_s, 3) avg_etime_s, status
from a
where sql_id in (
select sql_id
from(
select sql_id, count(distinct plan_hash_value)
from a
group by sql_id
having count(distinct plan_hash_value) > 1))
order by sql_id, date_time; spool off
使用方法介绍:
1.上传脚本到数据库服务器
2.执行sqlplus / as sysdba
3.执行 @脚本名字
4.会自动生成一个oracle_xj_实例名_日期.txt的文件,下载到本地就可以看了
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