- 博客(74)
- 收藏
- 关注
RSS订阅原创 Tokyo Cabinet与 Tokyo Tyrant
<br />Tokyo Cabinet 是日本人 Mikio Hirabayashi开发的一款 DBM 数据库，该数据库读写非常快，哈希模式写入100万条数据只需0.643秒，读取100万条数据只需0.773秒，是 Berkeley DB 等 DBM 的几倍。<br />Tokyo Cabinet 是一个DBM的实现。这里的数据库由一系列key-value对的记录构成。key和value都可以是任意长度的字节序列,既可以是二进制也可以是字符串。这里没有数据类型和数据表的概念。<br />当做为Hash表数据
2010-06-11 21:47:00
479
原创 memcached相关技术
<br />1.概述<br /> <br /> Memcached 是一个高性能的分布式内存对象缓存系统，用于动态Web应用以减轻数据库负载。它通过在内存中缓存数据和对象来减少读取数据库的次数，从而提供动态、数据库驱动网站的速度。Memcached基于一个存储键/值对的hashmap。其守护进程（daemon ）是用C写的，但是客户端可以用任何语言来编写，并通过memcached协议与守护进程通信。但是它并不提供冗余（例如，复制其hashmap条目）；当某个服务器S停止运行或崩溃了，所有存放在S上
2010-06-11 21:33:00
358
原创 Capture the total CPU consumptions for an Instance
Create a file as bellow named cpu.sh--------------------:/u01/app/oracle=>cat cpu.sh for para1 in $*dotcpu=`ps -afe -o user -o pcpu -o comm -o args | grep $ORACLE_SID|cut -c10-14 |awk {ounces += $
2007-12-04 13:01:00
457
转载 Shows the reason for multiple statement childs in shared pool
rem output only those statements that have more than 5 versions:define versions=5select version_count,address,hash_value,parsing_schema_name,reason,sql_text from (selectaddress,||decode(max(
2007-03-27 13:24:00
806
转载 Explain plan for last executed statement
define plan_table=PLAN_TABLEset linesize 132 pagesize 1000 feedback off verify off column statement_id new_value statement_idcolumn prev_sql_addr new_value sql_addrselect prev_sql_addr||/||prev_chil
2007-03-27 13:07:00
658
转载 Opt_param: a new optimizer hint for 10gR2
"OPT_PARAM" is a new optimizer hint introduced in 10gR2. This hint behaves the same way as setting a parameter (e.g, using alter session) but the effect is for the next statement only. Two IN params a
2007-02-27 21:56:00
932
原创 put your own progress information in V$SESSION_LONGOPS
If only more developers used the DBMS_APPLICATION_INFO package. As a DBA I often see requests to investigate why a particular job is taking longer than expected, or to kill a session running a partic
2007-02-27 21:50:00
1132
转载 show log file info and log switches
column day format a16 heading Daycolumn d_0 format a3 heading 00column d_1 format a3 heading 01column d_2 format a3 heading 02column d_3 format a3 heading 03column d_4 format
2007-02-27 21:38:00
997
转载 How to return a long columns size
create or replace function getLongsize (p_query varchar2) return number as v_cursor integer default dbms_sql.open_cursor; i number; v_temp varchar2(250); v_returne
2007-02-24 22:02:00
625
转载 Retreive new hashvalue and display their load
alter session set nls_territory=france;alter session set nls_numeric_characters=", ";WITHp AS ( SELECT to_date(24/01/07 06:00,DD/MM/YY HH24:MI) /* First start date to compare */ b
2007-02-14 13:26:00
760
转载 Quick check of asm disk space
#!/bin/bash. /home/oracle/set_oraenvsid="+ASM1"echo "Check Space on "$sidexport ORACLE_SID=$sidasmcmd lsdgEOF !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
2007-02-14 13:23:00
631
转载 Complete sessions information
SELECT SID, serial#, username, (SELECT holding_session FROM dba_waiters WHERE waiting_session = s.SID AND ROWNUM = 1 AND holding_session NOT IN (
2007-02-14 13:20:00
700
转载 List sessions and some details about them
set linesize 145set pagesize 1000set trimout onset trimspool onSet Feedback offset timing offset verify offpromptprompt -- ----------------------------------------------------------
2007-02-14 13:18:00
708
转载 How to divide a data set into equal size buckets
Install scripts:drop table INTERVALS/create table INTERVALS(NAME varchar2(100), sal number(10,2))/insert into intervals(NAME,sal)select object_name, dbms_random.value(0,100) from all_objects/commit//*
2007-02-07 21:09:00
661
转载 db duplication (and datafile renaming)
* jijo.sql|| mauro rossolato, 2006|| || >>> FOR DB DUPLICATION || you can use RMAN (copy) or operating system copy command (dd or ocopy)|| In addition creates a controlfile creation script.|| |||| Ma
2007-02-07 21:04:00
721
转载 Quickly check the i/o throughput
SET linesize 132 pagesize 1000column file_name format A60DROP TABLE tmp_iostats_1;REM *** get first snapshot ***create table tmp_iostats_1 as select SYSDATE snaptime,D filetype,t.* from
2007-02-02 13:04:00
506
转载 Remove a job without connecting as job owner
In order to use dbms_job.rmove, you must be connected as the owner of the job. As DBA, you want to remove another user job: - create a procedure owned by the user that does an execute immediate - call
2007-01-24 18:52:00
695
转载 This script allows capturing and storing occured errors
------------------------------------------------------------------------------------- Filename: log_errors.sql --- Purpose: captures all database errors and writes error --- message a
2007-01-16 12:59:00
588
转载 Database realtime monitoring
create or replace type MySysstat as object ( REDO_BLOCKS NUMBER, LOGICAL_READS NUMBER, BLOCK_CHANGES NUMBER, PHYSICAL_READS NUMBER, PHYSICAL_WRITES NUMBER, USER_CALLS NUMBER, PARSES NUMBER, H
2007-01-16 12:57:00
604
转载 display a history load for a hash_value
WITH p AS (SELECT sysdate-5 /* start date */ bsnap , sysdate /* end date */ esnap, 2383739701 /* hash value */ hashv
2007-01-16 12:55:00
499
转载 Script to see invalid object (and unusable indexes)
set linesize 145set pagesize 1000set trimout onset trimspool onSet Feedback offset timing offset verify offpromptprompt -- ----------------------------------------------------------
2007-01-16 12:50:00
564
转载 Sql tricks: multiple rows in one output value
Hi, I was asked once how to make an SQL that will return the following result: DEPTNO NAME_LIST 1 Komers,Mokrel,Stenko 2 Hung,Tong 3 Hamer 4 Mansur from: LNAME DEPTNO Komers 1 Stenko 1 Mokrel 1 Hung 2
2007-01-13 16:14:00
653
转载 tablespace occuped with autoextent managment and tempfile
SELECT ddf.tablespace_name, SUM( distinct ddf.ddfbytes ) / 1048576 maxpossible, SUM( NVL( ds.dsbytes , 0 ) / 1048576 ) occuped ,(SUM( distinct ddf.ddfbytes )/ 1048576) - SUM( NVL( ds.dsby
2007-01-13 16:11:00
666
转载 Trace event to check explain plan + bind variable peeking + hints + CBO environment
Here is description and example about usefull event in 10g: ORA-10132 dump plan after compilation When events 10046 level 4 and 10053 are too verbose, this event dumps - for each parsed query: - th
2007-01-13 16:09:00
621
转载 Creating a Data dictionary file to use with LogMi
Creating the Dictionary File To use LogMiner to analyze joedevo’s data, you must create a dictionary file before starting LogMiner. Take the following steps: 1. In the init.ora file, set the initializ
2007-01-13 16:06:00
827
转载 How to change SYSDATE's value to a static date without changing system date
First change the NLS_DATE_FORMAT to a recognizable full format: alter session set nls_date_format = dd.mon.yyyy hh24:mi:ss; Then change the system variable fixed_dates value: alter system set fixed
2007-01-12 13:47:00
459
转载 size tablespace autoextend and temp managed
SELECT tablespace_name, round(SUM(used)/1024/1024) USED_MB,round((SUM(total)/1024/1024),0) MAXSIZE_MB,TO_CHAR(100*SUM(used)/SUM(total),999,99)|| % Pct_Used FROM ( SELECT what,tablesp
2007-01-12 13:42:00
621
转载 Finding duplicate indexes
Ive seen a note on deleting duplicate indexes! This should be done very carefuly, as some indexes can have same leading column, but are both needed! Here is a script that will help you find indexes w
2007-01-12 13:37:00
428
转载 creating recovery catalog
create a recovery catalog The simple steps to create a recovery catalog in rman is as below:- OUTLINE: 1). Create tablespace 2). Create catalog owner 3). Grant privileges 4). Create catalog 5). Connec
2006-12-16 13:42:00
590
转载 Check if index is fragmented (needs reorg or coalesce)
define owner=FRANCK -- table ownerdefine table=SALES -- table namedefine index=SALES_TIME -- index namedefine buckets=10 -- number of bucketsdefine sampl
2006-12-16 13:38:00
659
转载 v$datafile_header related mistake in 9i OCP book
hi as mentioned in oracle 9i DBA FUNDAMENTALS-2 book that when you put a tablespace in begin backup mode.the FUZZY column in V$datafile_header set to YES...............(it was the case before oracle 9
2006-12-16 13:34:00
576
转载 Rename DB with NID
Rename Database 9i and above Check the Db name SQL> select name from v$database; NAME --------- SUN START : 1.shutdown immediate 2.startup mount 3.$nid target=sys as sysdba dbname=orcl setname=yes OUT
2006-11-24 12:45:00
688
转载 Improving SQL efficiency using CASE
IntroductionSome time ago I wrote "The Power of Decode", a paper on using the DECODE function to improve report performance. I was aware at the time that DECODE was being replaced by CASE but wanted
2006-11-24 12:43:00
548
转载 Reducing CPU problem caused due to high buffer gets (after large delete)
Reducing CPU problem caused due to high buffer gets. Couple of month’s back I was working on tuning one of the telecom databases which was occupying almost 90% of the CPU in peak times. While interpre
2006-11-14 13:16:00
670
转载 using INSTR function for obtaining data from a table, based on a selection from the master table (FK relation)
Suppose that we have a departments table (dep_id, dep_name,...) and another table with persons from every department (person_id, dep_id,...). If many operations are required on the data from the perso
2006-11-14 13:14:00
532
原创 常用网址
1. http://www.embhelp.com/download/嵌入式系统文档及程序下载2.http://www.smartchaps.com/articles.htmlArticles, presentations, whitepapers and scripts written by Tanel are featured here.Most of these materia
2006-11-12 13:55:00
563
转载 arm开发
第一章 STARTUP 1 ARM的启动 一般的嵌入式系统在主程序执行之前都需要执行一些初始化的过程以创造嵌入式程序运行的环境，尤其是一些高级的嵌入式系统，由于核心芯片使用内存映射、内存保护等机制以及编程使用高级语言C,C++甚至JAVA语言，都需要先创建一个适合程序运行的硬件环境，然后初始化或者配置或者剪裁run-time library, 这些工作都必须在主程序运行前完成，所以一个startu
2006-11-12 13:45:00
581
原创 建立针对arm-linux的交叉编译环境
交叉编译环境介绍 交叉编译是嵌入式开发过程中的一项重要技术，它的主要特征是某机器中执行的程序代码不是在本机编译生成，而是由另一台机器编译生成，一般把前者称为目标机，后者称为主机。采用交叉编译的主要原因在于，多数嵌入式目标系统不能提供足够的资源供编译过程使用，因而只好将编译工程转移到高性能的主机中进行。 linux下的交叉编译环境重要包括以下几个部分： 针对目标系统
2006-11-12 13:16:00
928
转载 Locks tree sessions
This script displays information on all database sessions with the username column displayed as a heirarchy if locks are present. It is assumed that the user running the script has access to the V$ vi
2006-11-04 21:58:00
514
空空如也
空空如也
TA创建的收藏夹 TA关注的收藏夹
TA关注的人