当前位置: 首页 > 图文教程 > 数据库 > Oracle > Performance Improvement Tips for Oracle on UNIX

Oracle
Oracle常用dump命令,记录一下备查。
Oracle存储过程之数据库中获取数据实例
Oracle存储过程入门学习基本语法
java.sql.SQLException: 内部错误: Unable to construct a Datum from the specified input
Oracle 函数大全[字符串函数,数学函数,日期函数]
Oracle 自增(auto increment) 或 标识字段的建立方法
oracle 存储过程加密的方法
Oracle针对数据库某一行进行操作的时候,如何将这一行加行锁
Oracle 忘记密码的找回方法
Oracle 数据库导出(exp)导入(imp)说明
oracle 常见等待事件及处理方法
Oracle9i 动态SGA,PGA特性探索
PDO取Oracle lob大字段,当数据量太大无法取出的问题的解决办法
ORACLE 数据库RMAN备份恢复
用Mimer Validator检查SQL查询
oracle执行cmd的实现方法
ORACLE 正则解决初使化数据格式不一致
Oracle 触发器的使用小结
oracle 时间格式的调整
Oracle 10g的DBA无法登录解决方案

Performance Improvement Tips for Oracle on UNIX


出处:互联网   整理: 软晨网(RuanChen.com)   发布: 2009-10-31   浏览: 52 ::
收藏到网摘: n/a

TIMED_STATISTICS = true

  1. Restart your database. 
  2. Run your application.
  3. Run tkprof against the tracefile created by your application:

tkprof EXPLAIN=username/passwd

  1. Look at formatted output of trace command and make sure that your

      SQL statement is using indexes correctly.  Refer to DBA guide for a list

      of rules that the oracle optimizer uses when choosing a path for a SQL statement. 

                 <<<<<< OUTPUT OF TKPROF FILE >>>>>>> 

count   = number of times OPI procedure was executed 

cpu     = cpu time executing in hundredths of seconds 

elap    = elapsed time executing in hundredths of secs 

phys    = number of physical reads of buffers (from disk) 

cr      = number of buffers gotten for consistent read 

cur     = number of buffers gotten in current mode (usually for update) 

rows    = number of rows processed by the OPI call 

===========================================================

select * from emp where empno=7369  

            count     cpu    elap    phys      cr     cur    rows 

Parse:          1       0       0       0       0       0 

Execute:        1       0       0       0       0       2       0 

Fetch:          1       0       0     219     227       0       2 

Execution plan: 

TABLE ACCESS (FULL) OF EMP 

===========================================================

select empno from emp where empno=7934  

            count     cpu    elap    phys      cr     cur    rows 

Parse:          2       0       0       0       0       0 

Execute:        2       0       0       0       0       2       0 

Fetch:          2       0       0       0&nb