安装unixODBC： 安装：yum install unixODBC* 查看安装了哪些依赖包：rpm -qa |grep unixODBC
安装mysql-connector： 下载： https://dev.mysql.com/downloads/connector/odbc/ https://dev.mysql.com/get/Downloads/Connector-ODBC/8.0/mysql-connector-odbc-8.0.11-1.el6.x86_64.rpm 将mysql-connector-odbc-8.0.11-1.el6.x86_64.rpm放在 /usr/local 目录下。 安装：rpm -ivh mysql-connector-odbc-8.0.11-1.el6.x86_64.rpm
ODBC配置： vi /etc/odbc.ini 说明：User 、Password、Database分别为mysql数据库的用户名、密码、数据库
[dg4odbc] Description = ODBC for MySQL Driver = /usr/lib64/libmyodbc8w.so Server = 192.168.71.90 Port = 3306 User = dbtest Password = 123456 Database = testodbc连通性测试： isql dg4odbc -v ±--------------------------------------+ | Connected! | | | | sql-statement | | help [tablename] | | quit | | | ±--------------------------------------+
4.Oracle数据库相关配置 （1）vi /opt/oracle/product/112010/db_1/hs/admin/initdg4odbc.ora 已有内容注释掉，添加如下内容。这里配置的是数据库实例名、odbc lib包、odbc配置文件路径
HS_FDS_CONNECT_INFO = dg4odbc HS_FDS_TRACE_LEVEL = off HS_FDS_SHAREABLE_NAME = /usr/lib64/libodbc.so set ODBCINI= /etc/odbc.ini（2）配置监听文件，给mysql重新配置一个监听： vi /opt/oracle/product/112010/db_1/network/admin/listener.ora
SID_LIST_LISTENER1 = (SID_LIST = (SID_DESC = (SID_NAME = dg4odbc) (ORACLE_HOME = /opt/oracle/product/112010/db_1) (PROGRAM = dg4odbc) ) ) LISTENER1 = (DESCRIPTION_LIST = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.71.90)(PORT = 1522)) ) ) ADR_BASE_LISTENER1 = /opt/oracle启动监听（需要切换到oracle用户下：su - oracle）： [root@localhost ~]# su - oracle [oracle@localhost ~]$ lsnrctl LSNRCTL> start listener1 LSNRCTL> stop listener1
（只有一个监听的启动和停止：lsnrctl start/stop）
（3）配置tnsname：vi /opt/oracle/product/112010/db_1/network/admin/tnsnames.ora
dg4odbc = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.71.90)(PORT = 1522)) ) (CONNECT_DATA = (SERVICE_NAME = dg4odbc) ) (HS = OK) ) 用oracle连接工具创建dblink，使用管理员身份用户执行： create database link dg4odbc connect to "dbtest" identified by "123456" using 'dg4odbc';--注意使用单引号或者 先用管理员身份用户对业务用户授权，再用scott用户创建dblink
grant create database link to scott;注：如果在create之后加public(即create pubic database link……),则创建的dblink就是公共的,不加public就只有创建者可以使用了.
测试 select * from dual@dg4odbc; select * from test.table1@dg4odbc; insert into test.table1@"dg4odbc" values (2, '你好'); select m.*,m."aaa",m."bBb" from table1@dg4odbc m --注意区分大小写，否则报错：Oracle ORA-00904："xxx": 标识符无效大功告成。
原文参考：https://www.linuxidc.com/Linux/2018-04/152116.htm https://www.linuxidc.com/Linux/2015-11/124837.htm
