- 安装第二个数据库：
登录oracle用户进入家目录，添加配置环境变量：
vi .bash_profier
ORACLE_SID=prod2
- 临时环境变量：
$export ORACLE_HOME=/u01/app/oracle/product/11.2.0/db_1
$export ORACLE_SID=prod2
- 创建第二个数据库文件目录：
$mkdir -p /u01/app/oracle/oradata/prod2
- 创建sys用户密码文件：
$cd /u01/app/oracle/product/11.2.0/db_1/dbs
$orapwd file=orapwprod2 password=oracle
- 创建一个可读参数文件：
$vi initprod2.ora
添加：
DB_NAME=prod2
sga_target=500M
control_files='/u01/app/oracle/oradata/prod2/control01.ctl'
- 打开实例进入nomount模式，创建数据库系统proc，view ……：
SQL> sqlplus / as sysdba
SQL> startup nomount;
SQL> create spfile from pfile;
SQL> shutdown immediate;
SQL> startup nomount;
SQL> alter system set db_create_file_dest='/u01/app/oracle/oradata/prod2';
SQL> create database character set AL32UTF8 extent management local;
SQL> @?/rdbms/admin/catalog.sql;
SQL> @?/rdbms/admin/catproc.sql;
SQL> alter user system identified by oracle account unlock;
SQL> conn system/oracle
SQL> @?/sqlplus/admin/pupbld.sql;
- 验证实例：
SQL> show parameter name; NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
db_file_name_convert string
db_name string prod2
db_unique_name string prod2
global_names boolean FALSE
instance_name string prod2
lock_name_space string
log_file_name_convert string
service_names string prod2
- 多个数据库切换：. oraenv
[oracle@test ~]$ . oraenv
ORACLE_SID = [prod2] ? prod1
The Oracle base for ORACLE_HOME=/u01/app/oracle/product/11.2.0/db_1 is /u01/app/oracle
- 当再切入第二的环境变量的时候的，会无法自动识别oracle家目录，需手动输入地址，解决方法如下：
vi /etc/oratab（当用dbca窗口删库时，添加oratab文件后，dbca数据库列表会显示数据库名）
添加到最后一行参数：（Y代表支持dbstart和dbshut启停数据库）
prod2:/u01/app/oracle/product/11.2.0/db_1:Y
# This file is used by ORACLE utilities. It is created by root.sh
# and updated by the Database Configuration Assistant when creating
# a database. # A colon, ':', is used as the field terminator. A new line terminates
# the entry. Lines beginning with a pound sign, '#', are comments.
#
# Entries are of the form:
# $ORACLE_SID:$ORACLE_HOME:<N|Y>:
#
# The first and second fields are the system identifier and home
# directory of the database respectively. The third filed indicates
# to the dbstart utility that the database should , "Y", or should not,
# "N", be brought up at system boot time.
#
# Multiple entries with the same $ORACLE_SID are not allowed.
#
#
prod1:/u01/app/oracle/product/11.2.0/db_1:Y
prod2:/u01/app/oracle/product/11.2.0/db_1:Y
- 演示1：
[oracle@test ~]$ ps -ef|grep smon
oracle 11062 1 0 00:25 ? 00:00:00 ora_smon_prod2
oracle 12799 12285 0 02:12 pts/2 00:00:00 grep smon
[oracle@test ~]$ dbshut
ORACLE_HOME_LISTNER is not SET, unable to auto-stop Oracle Net Listener
Usage: /u01/app/oracle/product/11.2.0/db_1/bin/dbshut ORACLE_HOME
Processing Database instance "prod1": log file /u01/app/oracle/product/11.2.0/db_1/shutdown.log
Processing Database instance "prod2": log file /u01/app/oracle/product/11.2.0/db_1/shutdown.log
[oracle@test ~]$ ps -ef|grep smon
\oracle 12955 12285 0 02:12 pts/2 00:00:00 grep smon
- 演示2：
[oracle@test ~]$ . oraenv
ORACLE_SID = [prod2] ? prod1
The Oracle base for ORACLE_HOME=/u01/app/oracle/product/11.2.0/db_1 is /u01/app/oracle
[oracle@test ~]$ dbstart
ORACLE_HOME_LISTNER is not SET, unable to auto-start Oracle Net Listener
Usage: /u01/app/oracle/product/11.2.0/db_1/bin/dbstart ORACLE_HOME
Processing Database instance "prod1": log file /u01/app/oracle/product/11.2.0/db_1/startup.log
Processing Database instance "prod2": log file /u01/app/oracle/product/11.2.0/db_1/startup.log
[oracle@test ~]$ ps -ef|grep smon
oracle 13130 1 0 02:13 ? 00:00:00 ora_smon_prod1
oracle 13239 1 0 02:13 ? 00:00:00 ora_smon_prod2
oracle 13390 12285 0 02:14 pts/2 00:00:00 grep smon
[oracle@test ~]$ dbshut
ORACLE_HOME_LISTNER is not SET, unable to auto-stop Oracle Net Listener
Usage: /u01/app/oracle/product/11.2.0/db_1/bin/dbshut ORACLE_HOME
Processing Database instance "prod1": log file /u01/app/oracle/product/11.2.0/db_1/shutdown.log
Processing Database instance "prod2": log file /u01/app/oracle/product/11.2.0/db_1/shutdown.log
[oracle@test ~]$ ps -ef|grep smon
oracle 13550 12285 0 02:14 pts/2 00:00:00 grep smon
- 监听器没有受到快捷启停命令的影响：
[oracle@test ~]$ ps -ef|grep lsnr
oracle 13609 1 0 02:18 ? 00:00:00 /u01/app/oracle/product/11.2.0/db_1/bin/tnslsnr LISTENER -inherit
oracle 13621 12285 0 02:19 pts/2 00:00:00 grep lsnr