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Oracle中如何查找消耗资源较大的SQL,
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从V$@L_502_0@AREA中查询最占用资源的查询
select b.username username,a.disk_reads reads,
a.executions exec,a.disk_reads/decode(a.executions,1,a.executions) rds_exec_ratio,
a.sql_text Statement
from v$sqlarea a,dba_users b
where a.parsing_user_id=b.user_id
and a.disk_reads > 100000
order by a.disk_reads desc;
用buffer_gets列来替换disk_reads列可以得到占用最多内存的sql语句的相关信息。
V$sql是内存共享sql区域中已经解析的sql语句。
列出使用频率最高的5个查询
select sql_text,executions
from (select sql_text,executions,
rank() over
(order by executions desc) exec_rank
from v$sql)
where exec_rank <=5;
消耗磁盘读取最多的sql top5
select disk_reads,sql_text
from (select sql_text,disk_reads,
dense_rank() over
(order by disk_reads desc) disk_reads_rank
from v$sql)
where disk_reads_rank <=5;
找出需要大量缓冲读取(逻辑读)操作的查询
select buffer_gets,sql_text from (select sql_text,buffer_gets,dense_rank() over (order by buffer_gets desc) buffer_gets_rank from v$sql) where buffer_gets_rank<=5;
原文链接:https://www.f2er.com/oracle/210417.html