一、环境
OS：Linux myhostname 2.6.9-42.ELsmp #1 SMP Sat Aug 12 09:39:11 CDT 2006 i686 i686 i386 GNU/Linux
CentOS release 4.4 (Final)
Oracle：Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Prod，数据库已经安装好
mysql：5.1.34-community for windows

二、安装配置
1. 安装unixODBC，用root用户
rpm -Uvh unixODBC-2.2.12-1.el4s1.1.i386.rpm
2. 安装mysql ODBC，用root用户
rpm -Uvh mysql-connector-odbc-5.1.5-0.i386.rpm
3. 安装oracle gateway，用oracle用户
我装的是10201_gateways_linux32.zip
unzip 10201_gateways_linux32.zip
cd gateways
./runInstaller
安装方法和oracle db 软件一样，我把gateway和db装一起了，共用一个OracleHOME
4. 配置/etc/odbc.ini
[DSName]
Driver =/usr/lib/libmyodbc5.so
Description =MySQL
Server =xxx.xxx.xxx.xxx
Port =3306
User =root
UID =root
Password = mypass
Database =mysqldbname
Option =3
Socket =
charset =utf8
测试ODBC
isql -v DSName root mypass
5. 配置$ORACLE_HOME/hs/admin/initDSName.ora
HS_FDS_CONNECT_INFO = DSName
HS_FDS_TRACE_LEVEL = 0
HS_FDS_SHAREABLE_NAME = /usr/lib/libmyodbc5.so
6. 配置listener.ora，加红色部分
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = /usr/u01/app/oracle/product/10.2.0/db_1)
(PROGRAM = extproc)
)
(SID_DESC =
(GLOBAL_DBNAME = BOSS)
(ORACLE_HOME = /usr/u01/app/oracle/product/10.2.0/db_1)
(SID_NAME = BOSS)
)
(SID_DESC =
(SID_NAME = phpcms)
(ORACLE_HOME = /usr/u01/app/oracle/product/10.2.0/db_1)
(PROGRAM = hsodbc)
)
)
7. 配置tnsnames.ora，添加
DSName =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.0.125)(PORT = 1521))
)
(CONNECT_DATA = (SERVICE_NAME = DSName))
(HS = OK)
)
8. 重启监听器并测试
lsnrctl reload
lsnrctl service
Service "DSName" has 1 instance(s).
Instance "DSName", status UNKNOWN, has 1 handler(s) for this service...
Handler(s):
"DEDICATED" established:3 refused:0
LOCAL SERVER
The command completed successfully
tnsping DSName
Attempting to contact (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.0.125)(PORT = 1521))) (CONNECT_DATA = (SERVICE_NAME = DSName)) (HS = OK))
OK (0 msec)
9. 建立dblink
CREATE PUBLIC DATABASE LINK linkname
CONNECT TO "root"
IDENTIFIED BY <PWD>
USING 'DSName';
10. 测试
select "name" from t1@linkname;
三、遗留问题
1. 字符集问题，最好oracle和mysql是utf8，否则中文有问题
2. text字段会报错：
select "textcol" from t1@linkname;
ORA-28500: 连接 ORACLE 到非 Oracle 系统时返回此信息:
[Generic Connectivity Using ODBC][MySQL][ODBC 5.1 Driver][mysqld-5.1.34-community]You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '"t1" WHERE "id"=1' at line 1 (SQL State: 37000; SQL Code: 1064)
ORA-02063: 紧接着 2 lines (起自 DSName)
本来想用datadirect的mysql ODBC试试，可只支持mysql enterprise版本，实在不好找，以后有机会再说吧。