[原]ORACLE 11g 通过odbc建立连接到mysql库的database link
以前做过在oracle通过gateway建立到sqlserver的database link（详情参见：http://blog.csdn.net/mchdba/article/details/52719278），现在需要无缝访问mysql，所以也需要建立类似这样的连接通道。
1、分配mysql账号
先在mysql库上建立连接账号：
GRANT SELECT ON test.* TO data_query@'192.168.129.%' IDENTIFIED BY 'data_query_1125'; |
2、安装dg4odbc
详细的gateways安装步骤参考http://blog.csdn.net/mchdba/article/details/52719278 里面的 “2、安装模块” 里面有详细的步骤描述。
在安装的时候，有一个关键的选择步骤就是选择odbc组件包进行安装，如下所示：E:\u\oracle\install\pic\11.png，
3、查看下安装的dg4odbc
[oracle@hch_test_121_61 ~]$ dg4odbc
Oracle Corporation --- TUESDAY NOV 15 2016 19:17:19.106
Heterogeneous Agent Release 11.2.0.1.0 - 64bit Production Built with Oracle Database Gateway for ODBC
[oracle@hch_test_121_61 ~]$ |
4、安装mysql组件
准备安装mysql客户端：yum install mysql-connector-odbc.x86_64 -y;
这样会安装一些依赖包主要是
mysql-connector*.x86_64.rpm
unixODBC*.x86_64.rpm
unixODBC*.i386.rpm
[root@hch_test_121_90 ~]# yum install mysql-connector-odbc.x86_64 -y Loaded plugins: fastestmirror, security Determining fastest mirrors * base: ftp.sjtu.edu.cn * extras: mirrors.163.com * updates: mirrors.163.com base | 3.7 kB 00:00 epel | 4.3 kB 00:00 epel/primary_db | 5.9 MB 00:06 extras | 3.4 kB 00:00 updates | 3.4 kB 00:00 updates/primary_db | 3.1 MB 00:00 zabbix | 951 B 00:00 zabbix-non-supported | 951 B 00:00 Setting up Install Process Resolving Dependencies --> Running transaction check ---> Package mysql-connector-odbc.x86_64 0:5.1.5r1144-7.el6 will be installed --> Finished Dependency Resolution
Dependencies Resolved
=============================================================================================================================================================================================== Package Arch Version Repository Size =============================================================================================================================================================================================== Installing: mysql-connector-odbc x86_64 5.1.5r1144-7.el6 base 114 k
Transaction Summary =============================================================================================================================================================================================== Install 1 Package(s)
Total download size: 114 k Installed size: 345 k Downloading Packages: mysql-connector-odbc-5.1.5r1144-7.el6.x86_64.rpm | 114 kB 00:00 Running rpm_check_debug Running Transaction Test Transaction Test Succeeded Running Transaction Installing : mysql-connector-odbc-5.1.5r1144-7.el6.x86_64 1/1 Verifying : mysql-connector-odbc-5.1.5r1144-7.el6.x86_64 1/1
Installed: mysql-connector-odbc.x86_64 0:5.1.5r1144-7.el6
Complete! [root@hch_test_121_90 ~]# |
5、配置odbc-mysql连接
[root@hch_test_121_90 ~]# more /etc/odbc.ini # Setup from the unixODBC64-libs package [rmt] Driver = /usr/lib64/libmyodbc5.so Server = 10.254.3.72 Port = 3306 User = data_query Password = data_query_1125 Database = test [root@hch_test_121_90 ~]# |
6、测试mysql组件的连接：
[root@hch_test_121_90 ~]# isql rmt +---------------------------------------+ | Connected! | | | | sql-statement | | help [tablename] | | quit | | | +---------------------------------------+ SQL> |
7、配置oracle连接
进去$ORACLE_HOME/hs/admin/，配置initrmt.ora
[oracle@hch_test_121_90 admin]$ more initrmt.ora HS_FDS_CONNECT_INFO=rmt # Data source name in odbc.ini HS_FDS_TRACE_LEVEL= debug HS_FDS_SHAREABLE_NAME=libodbc.so HS_FDS_SUPPORT_STATISTICS=FALSE HS_LANGUAGE=AMERICAN_AMERICA.WE8ISO8859P15 # # ODBC env variables set ODBCINI=/etc/odbc.ini HS_FDS_SHAREABLE_NAME=libodbc.so [oracle@hch_test_121_90 admin]$ |
配置$ORACLE_HOME/network/admin/listener.ora
SID_NAME is the DSN for the remote database.
ORACLE_HOME is the actual Oracle home file path.
PROGRAM tells Oracle to use heterogeneous services.
(SID_DESC = (SID_NAME = rmt) (ORACLE_HOME = /home/oracle/app/oracle/product/11.2.0/dbhome_1) (PROGRAM = dg4odbc) #(ENVS=LD_LIBRARY_PATH=/usr/lib64:/usr/lib:/home/orared/product/11.2.4/lib:/home/orared/product/11.2.4/odbc/lib) ) |
配置$ORACLE_HOME/network/admin/tnsnams.ora
rmtmysql = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.121.90 )(PORT = 1521)) ) (CONNECT_DATA = (SID = rmt) ) (HS = OK) ) |
8、建立dblink
create database link tg4mysql connect to data_query identified by "data_query_1125" using '(DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.121.90)(PORT = 1521)) ) (CONNECT_DATA = (SID = rmtmysql) ) (HS = OK) )'; |
测试：
SQL> select * from z_whs@tg4mysql; select * from z_whs@tg4mysql * ERROR at line 1: ORA-28545: error diagnosed by Net8 when connecting to an agent Unable to retrieve text of NETWORK/NCR message 65535 ORA-02063: preceding 2 lines from TG4MYSQL
SQL> |
解决办法：重启lsnrctl服务
9、问题ORA-28511
SQL> select * from Z_WHS@gwmysql; ERROR: ORA-28511: lost RPC connection to heterogeneous remote agent using SID=ORA-28511: lost RPC connection to heterogeneous remote agent using SID=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.121.90)(PORT =1521)))(CONNECT_DATA=(SID=rmt))) ORA-02063: preceding line from GWMYSQL Process ID: 20358 Session ID: 11 Serial number: 46988
no rows selected
SQL> |
再次查看：
SQL> select * from Z_WHS@gwmysql; ERROR: ORA-28511: lost RPC connection to heterogeneous remote agent using SID=ORA-28511: lost RPC connection to heterogeneous remote agent using SID=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.121.90)(PORT =1521)))(CONNECT_DATA=(SID=rmt))) ORA-02063: preceding line from GWMYSQL Process ID: 20497 Session ID: 134 Serial number: 41341
no rows selected
SQL> select ID,cname from Z_WHS@gwmysql; select ID,cname from Z_WHS@gwmysql * ERROR at line 1: ORA-00904: "CNAME": invalid identifier
SQL> select ID from Z_WHS@gwmysql;
ID ---------- 1 2 3
SQL>
|
为什么查询单个字段ID能查到记录，查询*查不出记录呢，查看Z_WHS表结构，发现有一个字段cname为小写，尝试改成大写字段，就可以查询出来了。
mysql> show create table Z_WHS; +-------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Table | Create Table | +-------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Z_WHS | CREATE TABLE `Z_WHS` ( `ID` bigint(20) NOT NULL DEFAULT '0' COMMENT '投诉主题表主键', `cname` varchar(16) DEFAULT NULL ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 | +-------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ 1 row in set (0.00 sec)
mysql> mysql> alter table Z_WHS change `cname` CNAME varchar(16) DEFAULT NULL;
Query OK, 0 rows affected (38.95 sec) Records: 0 Duplicates: 0 Warnings: 0
mysql> |
# PS：这个时候，oracle的网关对mysql的表是锁定状态，任何对mysql表的dml、ddl操作都会处于等待状态，如下所示：
| 13762502 | root | localhost | test | Query | 27 | Waiting for table metadata lock | alter table Z_WHS change `cname` CNAME varchar(16) DEFAULT NULL | |
|
需要在oracle的窗口退出来，释放掉通过网关对mysql的锁，才能让mysql窗口的alter语句sesseion会话得到这个表的使用权限来顺利执行完成alter操作。
BUT、但是，但是可惜的是alter语句执行完后，select cname 还是报一样的错误出来
新添加一列数字列：
去mysql库添加数字列 mysql> alter table Z_2 add column NUM int; Query OK, 0 rows affected (0.07 sec) Records: 0 Duplicates: 0 Warnings: 0
mysql> update Z_2 set NUM=1; Query OK, 1 row affected (0.00 sec) Rows matched: 1 Changed: 1 Warnings: 0
mysql>
再通过gateway查询结果： SQL> conn dw/dwys0418 Connected. SQL> select ID,NUM from "Z_2"@gwmysql;
ID NUM ---------- ---------- 1 1
SQL> select ID,NUM,CN from "Z_2"@gwmysql; ERROR: ORA-28511: lost RPC connection to heterogeneous remote agent using SID=ORA-28511: lost RPC connection to heterogeneous remote agent using SID=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.121.90)(PORT =1521)))(CONNECT_DATA=(SID=rmt))) ORA-02063: preceding line from GWMYSQL Process ID: 21333 Session ID: 11 Serial number: 47108
no rows selected
SQL> |
问题依旧，等待后续进一步解决。