|   |   |
|---|---|
|XE下载|[https://www.oracle.com/database/technologies/xe-downloads.html](https://www.oracle.com/database/technologies/xe-downloads.html)|
|下载地址|[https://www.oracle.com/database/technologies/oracle-database-software-downloads.html#db_free](https://www.oracle.com/database/technologies/oracle-database-software-downloads.html#db_free)|
 
XE是单实例 CPU 内存闲置
 
==#Oracle Linux 8== ==预安装【====配置用户和权限以及依赖====】==  
dnf install oracle-database-preinstall-19c
 
==#====安装数据库【====注意必须和预安装匹配====】==  
sudo yum localinstall oracle-database-ee-19c-1.0-1.x86_64.rpm
 
==#====初始配置数据库==  
/etc/init.d/oracledb_ORCLCDB-19c configure
 
==#====使用====cat== ==查看配置日志==  
/opt/oracle/cfgtoollogs/dbca/ORCLCDB/ORCLCDB.log
 
==#L====inux====操作环境配置【====.bash_profile== ==&== ==文件地址不固定】==  
export ORACLE_HOME=/opt/oracle/product/19c/dbhome_1  
export PATH=$PATH:$ORACLE_HOME/bin
 
==#linux====配置实例==  
export ORACLE_SID=ORCLCDB  
==#windows====配置实例==  
set oracle_sid=ORCLCDB
 
==#====连接服务器==  
Sqlplus / as sysdba  
sqlplus sys@localhost:1521/FREEPDB1 as sysdba
 
==#====关闭防火墙==  
systemctl stop firewalld  
systemctl disable firewalld  
systemctl status firewalld
 21. ==检查防火墙状态，使用以下命令：============sudo firewall-cmd== ==--state========如果防火墙处于活动状态，您需要将端口1521添加到防火墙规则。如果防火墙处于不活动状态，则无需进行任何更改。==
22. ==如果防火墙处于活动状态，添加一个新的防火墙规则以允许通过端口1521的连接，使用以下命令：============sudo firewall-cmd== ==--permanent--zone=====public== ==--add-port=========1521====/tcp== ======这将在"public"区域添加一个永久规则，允许TCP协议的1521端口连接。==
23. ==重新加载防火墙配置，使更改生效：============sudo firewall-cmd== ==--reload========现在，防火墙将允许通过端口1521的连接。==    
==#====解锁====system==  
alter user system account unlock;
 
==#====修改====system====密码==  
ALTER USER system IDENTIFIED BY "19841122Cy";
   

==#====查看监听情况==  
lsnrctl status ==/start==
   

==#====查看当前实例名称和状态==  
SELECT INSTANCE_NAME, STATUS FROM V$INSTANCE;
 
#查询所有实例（需要先连接一个实例）  
SELECT inst_id, instance_name, host_name, version, status FROM gv$instance;
 
==#====查看实例用户==  
SELECT USERNAME FROM DBA_USERS;
 
==#====创建用户和密码==  
CREATE USER zhensolid01 IDENTIFIED BY 19841122Cy;  
==#====分发读取权限==  
GRANT CONNECT, SELECT, SELECT_CATALOG_ROLE TO zhensolid;
 
==#== ==查看保留字母==  
SELECT KEYWORD  
FROM V$RESERVED_WORDS;
 
==#====显示当前会话所连接的容器名称==  
show con_name;
 
==#====显示当前数据库中所有的插件式数据库（====PDB====）的信息。==  
show pdbs;
 
==#====打开容器==  
ALTER PLUGGABLE DATABASE ==ORCLPDB1== OPEN;
 
==#====切换容器==  
ALTER SESSION SET CONTAINER = ==ORCLPDB1==;
 
#查看容器信息  
SELECT NAME, CON_ID, DBID, GUID, OPEN_MODE FROM V$CONTAINERS WHERE NAME = =='ORCLPDB1'==;