December 11, 2011 oracle, RAC No comments RAC
环境：redhat 5.5+oracle 10g rac+netapp
首先碰到DMM问题，netapp存储通过DMM软件mapping过来的设备 oracle无法识别 报如下错误：
the location /dev/mapper/ocr1 ,entered for the oracle cluster registry(OCR) is not shared across all the nodes in the cluster…
起初怀疑是device 无法共享， 分别在两个node进程dd if-of操作 发现导入内容在另一个节点可以识别，确保磁盘是共享的，查看mu[……]
December 9, 2011 oracle, RAC No comments RAC
在安装rac之前，可以通过Oracle提供的一个工具进行cluster环境验证，这个工具叫做cluvfy（Cluster Verification Utility)。
一、CVU程序的位置
OTN下载: http://otn.oracle.com/RAC
Oracle DVD
–clusterware/cluvfy/runcluvfy.sh
–clusterware/rpm/cvuqdisk-1.0.1-1.rpm (linuxonly)
CRS Home (如果已安装CRS软件)
–/bin/cluvfy
–/cv/rpm/cvuqdisk-1[……]
December 7, 2011 maintain, oracle, replication 2 comments 11g
今天在生产库解决一个ORA-01555 on Active Physical standby问题：
Applies to:
Oracle Server – Enterprise Edition – Version: 11.2.0.2.0 and later [Release: 11.2 and later ]
Information in this document applies to any platform.
Primary and Standby databases at 11.2.0.2
Symptoms
After upgrading to 11.2.0[……]
December 7, 2011 Internals, oracle No comments 备份恢复
[oracle@liu dbs]$ sqlplus ‘/as sysdba’
SQL*Plus: Release 10.2.0.1.0 – Production on Wed Dec 7 00:06:50 2011
Copyright (c) 1982, 2005, Oracle. All rights reserved.
Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 – Production
With the Partitioning, OLAP and Data Mini[……]
December 6, 2011 maintain, oracle No comments sqlldr
在使用sqlldr工具导入数据的时候 往往需要将导入的某列按顺序排列,我们可以使用sqlldr 的虚拟列功能实现
[oracle@liu ~]$ sqlplus ‘/as sysdba’
SQL*Plus: Release 10.2.0.1.0 – Production on Tue Dec 6 11:00:55 2011
Copyright (c) 1982, 2005, Oracle. All rights reserved.
Connected to:
Oracle Database 10g Enterprise Edition Release 10.[……]
December 4, 2011 oracle, replication No comments dataguard
一. 确认操作的对象和语句是否能被逻辑Standby支持
1.1 由于逻辑Standby是通过SQL应用来保持与Primary数据库的同步。SQL应用与REDO应用是有很大的区别，REDO应用实际上是在物理Standby端进行RECOVER；SQL应用则是分析重做日志文件中的REDO信息，并将其转换为SQL语句，在逻辑Standby端执行，因此，需要注意以下几点：
（1）并非所有的数据类型都能被逻辑Standby支持，
逻辑Standby支持的数据类型有：
BINARY_DOUBLE、BINARY_FLOAT、BLOB、CHAR、CLOB and NCLOB、 DATE、INT[……]
December 4, 2011 maintain, oracle 2 comments oracle lock
Oracle中的锁，一共有6种模式：
0：none
1：null 空
2：Row-S 行共享(RS)：共享表锁，sub share
3：Row-X 行独占(RX)：用于行的修改，sub exclusive
4：Share 共享锁(S)：阻止其他DML操作，share
5：S/Row-X 共享行独占(SRX)：阻止其他事务操作，share/sub exclusive
6：exclusive 独占(X)：独立访问使用，exclusive
Example Tables
The lock waits which can occur are demonstrat[……]
在使用expdp导出数据时，可以使用estimate参数控制并且估算导出文件大小,estimate取值分为blocks 和statistics两种，下面记录两者的差异：
expdp liu/liu directory=dump tables=estimate_sts query=estimate_sts:'”where id>10000″‘ estimate=statistics
expdp liu/liu directory=dump tables=estimate_blk query=estimate_blk:'”where t1>2000″‘ estimate=statistic[……]
December 2, 2011 oracle, replication No comments bug
今天用10.2.0.1的一套物理DG 转 逻辑 standby 出现大量错误：
primary 端：
— Connected User is Valid
RFS[2]: Assigned to RFS process 30286
RFS[2]: Database mount ID mismatch [0x9a9ac2b3:0x9a9a1a16]
RFS[2]: Destination database ID mismatch [0x2593781616:0x2592975883]
RFS[2]: Not using real application cluste[……]
December 1, 2011 network, oracle No comments
Applies to:
Oracle Net Services – Version: 11.1.0.6 to 11.2.0.2 – Release: 11.1 to 11.2
Oracle Server – Enterprise Edition – Version: 11.1.0.6 to 11.2.0.2 [Release: 11.1 to 11.2]
Information in this document applies to any platform.
TNS-12170, ORA-12170, TNS-12535, TNS-00505 alert.log
Sympt[……]