在10gR2中,oracle简化了stream的配置的全过程,在9iR2及10gR1中,需要针对stream的捕获、传播、应用进程进行配置的步骤
已经被dbms_streams_adm新提供的过程(pre_instantiation_setup/post_instantiation_setup)给封装起来啦,
配置stream只需要调用两个存储过程就可以搞定啦,真是太激动人心啦,下面简单地介绍一下dbms_streams_adm的新过程的用法。
1.在stream进行配置前,需要做些准备工作
a 源库与目标库初始化参数的设置
alter system set aq_tm_processes=4 scope=spfile;
alter system set job_queue_processes=5 scope=spfile;
alter system set global_names=true scope=spfile;
alter system set streams_pool_size=51m scope=spfile;
说明streams_pool_size在生产环境中最好>200m
b 源库与目标库tnsnames.ora配置
确保正确,可用tnsping通
c 源库与目标库复制管理员的创建
create user strmadmin identified by strmadminpw
default tablespace &tbs_name quota unlimited on &tbs_name;
grant connect, resource, dba to strmadmin;
d 源库与目标库创建互连的数据链
connect strmadmin/strmadminpw@test96;
create database link test99.net connect to strmadmin
identified by strmadminpw using 'test99';
connect strmadmin/strmadminpw@test99;
create database link test96.net connect to strmadmin
identified by strmadminpw using 'test96';
说明:必须确保双方的数据库链是可以连通.
用pre_instantiation_setup/post_instantiation_setup过程时
db link必须用db_name.domain的格式
e 源库与目标库必须处于归档模式
shutdown immediate;
startup mount;
alter database archivelog;
alter database open;
2.执行pre_instantiation_setup过程
在调用dbms_streams_adm的pre_instantiation_setup/post_instantiation_setup过程时, 它们必须成对出现,pre_instantiation_setup过程中,maintain_mode参数可取GLOBAL与 TRANSPORTABLE TABLESPACES,如果取GLOBAL时,表示全库复制,否则可以定义需要复制的表空间; perform_actions参数为TRUE,进行配置产生的源脚本将记录在dba_recoverable_*字典表, 如果pre_instantiation_setup执行时遇到错误,可以通过执行dbms_steams_adm的
recover_operation过程 在更正错误后继续执行复制配置; source_database/destination_database是我们已经创建好的dblink,必须确保正确啊, 否则pre_instantiation_setup过程将会失败,报ORA-23621错误,解决办法在后面会介绍; bi_directional参数设置为true时,表示是多源复制,即目标与源库双向同步, 否则即只从源库向目标库同步数据; exclude_schemas参数指需要排除在全库同步的表空间,多个表空间的话用逗号分开,
*表示排除配置stream时库中已经存在的表空间;
start_processes参数指配置完成后启动捕获及应用进程。
SQL>connect strmadmin/strmadminpw@test96;
declare
empty_tbs dbms_streams_tablespace_adm.tablespace_set;
begin
dbms_streams_adm.pre_instantiation_setup(
maintain_mode => 'GLOBAL',
tablespace_names => empty_tbs,
source_database => 'test96.net',
destination_database => 'test99.net',
perform_actions => true,
bi_directional => true,
include_ddl => true,
start_processes => true,
exclude_schemas => 'WMSYS,STRMADMIN,DBSNMP,TSMSYS,',
exclude_flags => dbms_streams_adm.exclude_flags_unsupported +
dbms_streams_adm.exclude_flags_dml + dbms_streams_adm.exclude_flags_ddl);
end;
/
如果参与复制的源库与目标库的db link等配置的正确,该过程将成功结束,
并且在strmadmin模式创建一系统用于复制的队列与字典表,如果db link配置出错,
执行pre_instantiation_setup过程时,将会报如下错误:
ORA-23621: Operation corresponding
3.用rman复制源库到目标库
a 对源库用rman进行备份,拷贝备份集与产生的归档到目标库,
并将目标库down下来,启动nomount状态。
rman nocatalog target /
rman>backup database;
rman>sql'alter system archive log current';
b 求得源库的scn
SQL>connect strmadmin/strmadminpw@test96;
SQL>set serveroutput on size 1000000
SQL>declare
until_scn number;
begin
until_scn:= dbms_flashback.get_system_change_number;
dbms_output.put_line('until scn: '||until_scn);
end;
/
until scn: 429596
c 用rman将源库复制到目标库
rman nocatalog target /
rman> connect auxiliary sys/sys@test99;
rman> run
{
set until scn 429596;
duplicate target database to 'TEST'
nofilenamecheck
open restricted;
}
d 重新命名目标库的global_name
alter database rename global_name to test99.net;
e 重新创建目标库的db link
connect strmadmin/strmadminpw@test99;
create database link test96.net connect to strmadmin
identified by strmadminpw using 'test96';
4.执行post_instantiation_setup过程
post_instantiation_setup也在源库执行,需要注意的参数是instantiation_scn
它的取值是我们从源库上获的scn的值-1=429595.
SQL>connect strmadmin/strmadminpw@test96;
SQL>declare
empty_tbs dbms_streams_tablespace_adm.tablespace_set;
begin
dbms_streams_adm.post_instantiation_setup(
maintain_mode => 'GLOBAL',
tablespace_names => empty_tbs,
source_database => 'test96.net',
destination_database => 'test99.net',
perform_actions => true,
bi_directional => true,
include_ddl => true,
start_processes => true,
instantiation_scn => 429595,
exclude_schemas => '*',
exclude_flags => dbms_streams_adm.exclude_flags_unsupported +
dbms_streams_adm.exclude_flags_dml + dbms_streams_adm.exclude_flags_ddl);
end;
/
在目标库禁止restricted session
SQL>connect sys/sys@test99.net as sysdba
SQL>alter system disable restricted session;
5.测试stream的配置结果
a 在test96上创建一个schema,并在该schema下创建一些对象,可以在test99上看到
b 在test99上创建一个schema,并在该schema下创建一些对象,可以在test96上看到
6 关于双向复制中avoid change cycling
查看目标库apply进程的tag:
COLUMN APPLY_NAME HEADING 'Apply Process Name' FORMAT A30
COLUMN APPLY_TAG HEADING 'Tag Value' FORMAT A30
SQL>connect sys/sys@test99 as sysdba;
SELECT APPLY_NAME, APPLY_TAG FROM DBA_APPLY;
Apply Process Name Tag Value
------------------------------ -----------
APPLY$_TEST96_42 010781
查看源库apply进程的tag:
COLUMN APPLY_NAME HEADING 'Apply Process Name' FORMAT A30
COLUMN APPLY_TAG HEADING 'Tag Value' FORMAT A30
SQL>connect sys/sys@test99 as sysdba;
SELECT APPLY_NAME, APPLY_TAG FROM DBA_APPLY;
Apply Process Name Tag Value
------------------------------ ------------------------------
APPLY$_TEST99_15 010498
说明:消除多源复制中的递归问题,stream中已经有很好的消除机制,
源端正常作业写入的redo entry的tag是NULL的,如果是由于源端的apply进程
产生的redo entry,在redo entry中将带有tag标志,这样在源端捕获进程在
捕获的redo entry中,过虑掉tag是NULL的,然后就可以消除change cycling.
10gR2stream全库复制
以上主要为大家介绍了pre_instantiation_setup/post_instantiation_setup过程在配置全库复制的方法,以下介绍dbms_streams_adm的maintain_global过程如何配置stream全库复制方法,适用于10gR2及以后版本。
1l.在stream进行配置前,需要做些准备工作
a 源库与目标库初始化参数的设置
alter system set aq_tm_processes=4 scope=spfile;
alter system set job_queue_processes=5 scope=spfile;
alter system set global_names=true scope=spfile;
alter system set streams_pool_size=51m scope=spfile;
说明streams_pool_size在生产环境中最好>200m
b 源库与目标库tnsnames.ora配置
确保正确,可用tnsping通
c 源库与目标库复制管理员的创建
create user strmadmin identified by strmadminpw
default tablespace &tbs_name quota unlimited on &tbs_name;
grant connect, resource, dba to strmadmin;
d 源库与目标库创建互连的数据链
connect strmadmin/strmadminpw@test96;
create database link test99.net connect to strmadmin
identified by strmadminpw using 'test99';
connect strmadmin/strmadminpw@test99;
create database link test96.net connect to strmadmin
identified by strmadminpw using 'test96';
说明:必须确保双方的数据库链是可以连通.
用pre_instantiation_setup/post_instantiation_setup过程时
db link必须用db_name.domain的格式
e 源库与目标库必须处于归档模式
shutdown immediate;
startup mount;
alter database archivelog;
alter database open;
f 源库与目标库必须创建directory
create directory dir_test96 as '/home/oracle/worksh';
create directory dir_test99 as '/home/oracle/worksh';
2.在源库执行MAINTAIN_GLOBAL过程
SQL>connect strmadmin/strmadminpw@test96;
begin
dbms_streams_adm.maintain_global(
source_directory_object => 'dir_test96',
destination_directory_object => 'dir_test99',
source_database => 'test96.net',
destination_database => 'test99.net',
perform_actions => true,
include_ddl => true,
instantiation => DBMS_STREAMS_ADM.INSTANTIATION_FULL_NETWORK);
end;
说明:在执行maintain_global时,源库与目标库必须创建directory,然后在源库执行, 目标库几乎什么都不用做,stream环境已经配置完毕。