一个监控脚本
create or replace directory TEMP_DIR as '/tmp';alter session set nls_date_format='yyyymmdd hh24:mi:ss';declarev_cpu_count number := 16;v_warn_value number := 10;v_monitor_interval number := 5;v_loop_c...
analyze与dbms_stat逻辑读对比测试
1. analyzeSQL> select segment_name,owner,segment_type,tablespace_name,bytes/1024/1024 from dba_segments where tablespace_name='TEST'; SEGMENT_NAME ...
rman备份集大小与segment大小的关系
一直认为rman备份集大小要与segment大小相当或比segment大,但在昨天下午的一次备份中发现,我这个想法是错误的。做个测试如下: 1. 创建一个空的测...
一个手工建库脚本
CREATE DATABASE testMAXINSTANCES 1MAXLOGHISTORY 1MAXLOGFILES 200MAXLOGMEMBERS 5MAXDATAFILES 500DATAFILE '/oracle/oradata/test/system01.dbf' SIZE 250MEXTENT MANAGEMENT LOCALDEFAULT TEMPORARY TABLESPACE...
session_cached_cursors
关于session_cached_cursors,metalink上有如下解释:Support and Historical Notes for "SESSION_CACHED_CURSORS" SESSION_CACHED_CURSORS that can be set that will help in situations where a user repeat...
提高数据加载速度(转)
Hypercharge Oracle data load speedThese notes document techniques for improving the speed of Oracle import (imp or impdp) and Oracle SQL*Loader (sqlldr) jobs. Also see my notes on tuning and im...
用一条sql创建一个日历(转)
SELECT LPAD( MONTH, 20-(20-LENGTH(MONTH))/2 ) MONTH,"Sun", "Mon", "Tue","Wed", "Thu", "Fri", "Sat"FROM (SELECT TO_CHAR(dt,'fmMonthfm YYYY') MONTH,TO_CHAR(dt+1,'iw') week,MAX(DECODE(TO_CHAR(dt,'d'),'1'...
驱动表测试
为了进行此次测试,需要加hints来指定驱动表,如下解释:ORDEREDThe ORDERED hint causes Oracle to join tables in the order in which they appear in the FROM clause.If you omit the ORDERED hint from a SQL...
进一步认识dataguard-(3)
1.最大保护模式配置。1.1确认是否有standby log。SQL> SELECT * FROM V$LOGFILE WHERE TYPE = 'STANDBY'; no rows selected1.2停止recover进程。SQL> alter database recover managed standby database cance...
索引学习五--物理组织对索引访问的影响
1. 创建2个测试表,一个表的数据按照顺序存放,另一个随机存放。sys@TEST>create table colocated(x int,y varchar2(80)); Table created. sys@TEST>begin 2 for i in 1 .. 100000 3&n...
进一步认识dataguard-(2)
1. 用rman创建dataguard(最大性能模式)1.1 强制启用日志SQL> ALTER DATABASE FORCE LOGGING;1.2 备份控制文件在primary上执行如下命令,创...
进一步认识dataguard-(1)
1.dataguard介绍1.1 dataguard配置一个dataguard系统由1个生产数据库和最多9个standby数据库组成。这些数据库通过oracle net连接到一起。在物理位置上没有限制。一个dataguard系统有以下两部分组成,primar...
索引学习四--降序索引
1. 建测试表s_table,并在empno和ename列上创建唯一索引scott@TEST>create table s_table as select * from test where empno<10; Table created. scott@TEST>create unique index idx_s on s_table(empn...
索引学习三-测试CBO与RBO对于索引使用的一个例子
1. 测试表test,执行一个查询,在empno列上创建了唯一索引,在没有做分析时,使用RBO生成执行计划:scott@TEST>select empno from test where empno>100 and empno<200 order by empno desc; Execution Plan--...
索引学习二—blevel
1. 在一个大表上创建唯一索引scott@TEST>create unique index idx_test on test(empno) nologging; Index created.2.分析该索引Elapsed: 00:00:58.58scott@TEST>exec dbms_stats.gather_index_stats(user,'I...
读书笔记-tunning101之share pool(二)
1. oracle提供了一个过程,能够将对象keep到shared_pool中。如下:SQL> exec dbms_shared_pool.keep('STANDARD'); PL/SQL procedure successfully completed. SQL> l 1 select namespace,name,ow...
读书笔记-tunning101之share pool(一)
part 1: 与shared pool相关的参数1. shared_pool_size :该参数设置了共享池的总大小,单位是字节。2. shared_pool_reserved_size: 该参数设定为较大对象使用的保留共享池大小。3.shared_pool_reserved_min...
9i和10g exp的一个区别
9i环境下测试如下:sys@TEST>select * from v$version; BANNER----------------------------------------------------------------Oracle9i Enterprise Edition Release 9.2.0.4.0 - ProductionPL/SQL Release...
rman数据迁移测试
1.以oracle用户身份,备份源数据库,脚本如下:run{allocate channel c1 type diskformat '/oracle/rman_bk/lev_0_%d_%T%s%p%u.bak';BACKUP database ;sql 'alter system switch logfile';}备份完毕后,修改备...
对export的CONSISTENT参数的一次测试
先来一段oracle document里对此参数的一段解释:Specifies whether or not Export uses the SET TRANSACTION READ ONLY statement to ensure that the data seen by Export is consistent to a single point in tim...