Oracle GoldenGate软件可以实现异构平台数据的迁移和同步,它是基于数据库日志结构变化,通过解析源端在线日志或归档日志获得数据
Oracle GoldenGate软件可以实现异构平台数据的迁移和同步,它是基于数据库日志结构变化,通过解析源端在线日志或归档日志获得数据增量,再将这些变化应用到目标数据库,从而实现源库和目标库的数据同步。下面通过一个简单的示例,详细介绍利用GoldenGate实现Oracle数据库之间的同步。
1. 安装
1.1 下载介质
GoldenGate的安装介质可以从Oracle的官网上下载。
1.2 配置GoldenGate用户
下载完成后将其拷贝到源和目标的数据库的相应位置解压完成后,,即可以开始进行配置。
# su – oracle
$ mkdir /u01/ogg
$ cd /u01/ogg
$ tar xvf ogg_for_oracle_linux_86.tar
注意,如果使用Oracle 11g的数据库,需要创建一个link文件。
$ ln -s /u01/app/oracle/product/11.2.0/db_1/lib/libnnz11.so -
/u01/app/oracle/product/11.2.0/db_1/lib/libnnz10.so
配置环境变量
$ vi ~/.bash_profile
添加如下的内容:
export ORACLE_BASE=/u01/app/oracle
export ORACLE_HOME=$ORACLE_BASE/product/10.2.0/db_1
export LD_LIBRARY_PATH=$ORACLE_HOME/lib:/u01/ogg
export GGATE=/u01/app/oracle/ogg
1.3 配置ogg的应用目录
使用ggsci工具,创建必要的目录。
$ cd /u01/app/oracle/ogg
$ ./ggsci
Oracle GoldenGate Command Interpreter for Oracle
Version 11.1.1.0.0 Build 078
Linux, x86, 32bit (optimized), Oracle 10 on Jul 28 2015 10:20:18
Copyright (C) 1995, 2010, Oracle and/or its affiliates. All rights reserved.
GGSCI (gridcontrol) 1> create subdirs
至此,GoldenGate基本的安装完成。
注意:此部分需要在源端和目标端完成。
2. 源数据库配置
GoldenGate主要通过抓取源端数据库重做日志进行分析,将获取的数据应用到目标端,实现数据同步。因此,为了让GoldenGate能够正常工作,源数据库需要进行一定配置。
2.1配置源数据库必须是 归档模式、附加日志、强制日志
--查看
SQL> CONN / AS SYSDBA
SQL>select db.LOG_MODE, db.SUPPLEMENTAL_LOG_DATA_MIN, db.FORCE_LOGGING
from v$database db
SQL>--修改
SQL>--1)archivelog
SQL>shutdown immediate
SQL>startup mount
SQL>alter database archivelog;
SQL>alter database open;
SQL>--2)force logging
SQL>alter database force logging;
SQL>--3)supplemental log data
SQL>alter database add supplemental log data;
2.2 关闭数据库的recyblebin
SQL>alter system set recyclebin=off scope=spfile;
如果数据库是10g,需要关闭recyclebin并重启;或者手工purge recyclebin。
2.3 配置复制的DDL支持
SQL>create user ogg identified by ogg default tablespace users temporary tablespace temp;
SQL>grant connect,resource,unlimited tablespace to ogg;
SQL>grant execute on utl_file to ogg;
SQL>@$GGATE/marker_setup.sql;
SQL>@$GGATE/ddl_setup.sql;
SQL>@$GGATE/role_setup.sql;
SQL>grant GGS_GGSUSER_ROLE to ogg;
SQL>@$GGATE/ddl_enable.sql;
2.4创建源端和目标端的测试用户
--在源端执行
SQL>create user ss identified by oracle default tablespace users temporary tablespace temp;
SQL>grant connect,resource,unlimited tablespace to ss;
--在目标上执行
SQL>create user rr identified by oracle default tablespace users temporary tablespace temp;
SQL>grant connect,resource,unlimited tablespace to rr;
3. 配置manager
在源端和目标端分别执行下面的步骤。
3.1 源端创建manager
[ogg@node1 gg]$ ./ggsci
GGSCI (node1) 1> info all
Program Status Group Lag Time Since Chkpt
MANAGER STOPPED
GGSCI (node1) 2> edit params mgr
PORT 7809
GGSCI(node1) 3> start manager
Manager started.
在目标端
[ogg@node2 gg]$ ./ggsci
GGSCI (node2) 1> info all
Program Status Group Lag Time Since Chkpt
MANAGER STOPPED
GGSCI (node2) 2> edit params mgr
PORT 7809
GGSCI(node2) 3> start manager
Manager started.
4. 配置源端复制队列
GGSCI (node1) 1> add extract ext1, tranlog, begin now
EXTRACT added.
GGSCI (node1) 2> add exttrail /u01/ogg/dirdat/lt, extract ext1
EXTTRAIL added.
GGSCI (node1) 3> edit params ext1
extract ext1
userid , password ogg
rmthost node1, mgrport 7809
rmttrail /u01/ogg/dirdat/lt
ddl include mapped objname sender.*;
table sender.*;
GGSCI (node1) 6> info all
Program Status Group Lag Time Since Chkpt
MANAGER STOPPED
EXTRACT STOPPED EXT1 00:00:00 00:10:55
5. 配置目标端同步队列
5.1 在目标端添加checkpoint表
[oracle@node2 ogg]$ ./ggsci
GGSCI (node2) 1> edit params ./GLOBAL –添加下列内容
GGSCHEMA ggate
CHECKPOINTTABLE ggate.checkpoint
GGSCI (node2) 2> dblogin userid ogg password ogg
Successfully logged into database.
GGSCI (node2) 3> add checkpointtable ogg.checkpoint
Successfully created checkpoint table GGATE.CHECKPOINT.

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