--在某个用户下找所有的索引 select user_indexes.table_name, user_indexes.index_name,uniqueness, column_name from user_ind_columns, user_indexes where user_ind_columns.index_name = user_indexes.index_name and user_ind_columns.table_name = user_indexes.table_name order by user_indexes.table_type, user_indexes.table_name, user_indexes.index_name, column_position; --监控表空间的I/O比例 select df.tablespace_name name,df.file_name "file",f.phyrds pyr,f.phyblkrd pbr,f.phywrts pyw, f.phyblkwrt pbw from v$filestat f,dba_data_files df where f.file#=df.file_id --监控 SGA 中字典缓冲区的命中率 select parameter, gets,Getmisses , getmisses/(gets+getmisses)*100 "miss ratio", (1-(sum(getmisses)/ (sum(gets)+sum(getmisses))))*100 "Hit ratio" from v$rowcache where gets+getmisses <>0 group by parameter, gets, getmisses; --监控 SGA 的命中率 select a.value + b.value "logical_reads", c.value "phys_reads", round(100 * ((a.value+b.value)-c.value) / (a.value+b.value)) "BUFFER HIT RATIO" from v$sysstat a, v$sysstat b, v$sysstat c where a.statistic# = 38 and b.statistic# = 39 and c.statistic# = 40; --监控内存和硬盘的排序比率,最好使它小于 .10,增加 sort_area_size SELECT name, value FROM v$sysstat WHERE name IN ('sorts (memory)', 'sorts (disk)'); --查看碎片程度高的表 SELECT segment_name table_name , COUNT(*) extents FROM dba_segments WHERE owner NOT IN ('SYS', 'SYSTEM') GROUP BY segment_name HAVING COUNT(*) = (SELECT MAX( COUNT(*) ) FROM dba_segments GROUP BY segment_name); --找使用CPU多的用户session select a.sid,spid,status,substr(a.program,1,40) prog,a.terminal,osuser,value/60/100 value from v$session a,v$process b,v$sesstat c where c.statistic#=12 and c.sid=a.sid and a.paddr=b.addr order by value desc; --监控log_buffer的使用情况:(值最好小于1%,否则增加log_buffer 的大小) select rbar.name,rbar.value,re.name,re.value,(rbar.value*100)/re.value||'%' "radio" from v$sysstat rbar,v$sysstat re where rbar.name='redo buffer allocation retries' and re.name='redo entries';
引用链接:http://blog.csdn.net/dongzhumao86/article/details/8480499