oracle利用透明网关访问mssql

　　遇到一个客户，有个需求，想将mssql中的数据抽取到oracle中。经过上网查找，感觉gateway这个工具可以实现，因此就搭建实验环境进行测试。首先在oracle delivery上面下载对应的安装包。

实验环境如下：

oracle数据库：

　　IP地址：192.168.56.100

　　数据库名称：orcl

　　数据库oracle_home：/u01/app/oracle/product/11.2.0/db_1

　　监听端口号：1521

gateway软件：

　　IP地址：192.168.56.100

　　gateway的home目录：/u01/app/gateway

　　SID名称：dg4msql

　　监听端口号：1523

mssql数据库：

　　IP地址：192.168.56.110

　　数据库名：MSDB

　　登录名：sa

　　密码：1qaz@WSX

上传刚才下载的软件包，将其随便解压在某个路径，在这里需要注意，我是把gateway和oracle安装在同一台服务器上，进入gateway，runInstaller开始安装：

[oracle@Abbott soft]$ cd gateways/
[oracle@Abbott gateways]$ ls
doc  install  legacy  response  runInstaller  stage  welcome.html
[oracle@Abbott gateways]$ export DISPLAY=192.168.56.1:0.0
[oracle@Abbott gateways]$ ./runInstaller

这里需要指定gateway的home名称和路径

安装for MSSQLSERVER的软件

指定要访问的数据库服务器IP地址，端口号，实例名和数据库名

在这里点击安装即可，

等安装结束后，运行如下脚本：

但是运行脚本时会有如下提示，这是因为我把gateway和oracle安装在了同一台服务器上，有些环境变量发生了冲突，直接回车，忽略：

[root@Abbott /]# /u02/app/gateway/root.sh
Running Oracle 11g root.sh script...

The following environment variables are set as:
    ORACLE_OWNER= oracle
    ORACLE_HOME=  /u02/app/gateway

Enter the full pathname of the local bin directory: [/usr/local/bin]:
The file "dbhome" already exists in /usr/local/bin.  Overwrite it? (y/n)
[n]:
The file "oraenv" already exists in /usr/local/bin.  Overwrite it? (y/n)
[n]:
The file "coraenv" already exists in /usr/local/bin.  Overwrite it? (y/n)
[n]: 

Entries will be added to the /etc/oratab file as needed by
Database Configuration Assistant when a database is created
Finished running generic part of root.sh script.
Now product-specific root actions will be performed.

点击OK之后会自动弹出配置监听的窗口，选择配置典型监听，然后下一步，安装完成之后推出即可：

接着查看配置文件情况，因为在安装软件的时候就指定了MSSQLSERVER的ip地址，端口号，数据库名等参数，所以这里不需要做什么修改。配置文件目录为gateway的home目录下面的$ORACLE_HOME/dg4msql/admin/initdg4msql.ora：

[oracle@Abbott admin]$ vi initdg4msql.ora
# This is a customized agent init file that contains the HS parameters
# that are needed for the Database Gateway for Microsoft SQL Server

#
# HS init parameters
#
HS_FDS_CONNECT_INFO=[192.168.56.110]:1433//MSDB
# alternate connect format is hostname/serverinstance/databasename
HS_FDS_TRACE_LEVEL=OFF
HS_FDS_RECOVERY_ACCOUNT=RECOVER
HS_FDS_RECOVERY_PWD=RECOVER

接着查看监听是否正常，进去之后看到没有配置静态监听，因此需要在这里添加一条静态静听（以下加黑标红部分请注意，这里的SID_NAME与配置文件的init+SID.ora中的SID要相同）。监听文件的路径为gateway_home目录下的/network/admin/listener.ora：

[oracle@Abbott admin]$ vi listener.ora
# listener.ora Network Configuration File: /u01/app/gateway/network/admin/listener.ora
# Generated by Oracle configuration tools.

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1523))
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.56.100)(PORT = 1523))
    )
  )

ADR_BASE_LISTENER = /u01/app/oracle

SID_LIST_LISTENER =
  (SID_LIST =
  (SID_DESC =
#   (GLOBAL_DBNAME = MSDB)
    (PROGRAM = dg4msql)
    (ORACLE_HOME = /u01/app/gateway)
    (SID_NAME = dg4msql)
  )
  )

这里如果直接使用lsnrctl status查看监听状态，查看到的是oracle数据库的监听，因此需要export ORACLE_HOME=/u01/app/gateway，然后再使用此命令：

[oracle@Abbott admin]$ lsnrctl start

LSNRCTL for Linux: Version 11.2.0.4.0 - Production on 04-JUL-2017 09:17:09

Copyright (c) 1991, 2013, Oracle.  All rights reserved.

Starting /u01/app/gateway//bin/tnslsnr: please wait...

TNSLSNR for Linux: Version 11.2.0.1.0 - Production
System parameter file is /u01/app/gateway/network/admin/listener.ora
Log messages written to /u01/app/gateway/diag/tnslsnr/Abbott/listener/alert/log.xml
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1523)))
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.56.100)(PORT=1523)))

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1523)))
STATUS of the LISTENER
------------------------
Alias                     LISTENER
Version                   TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date                04-JUL-2017 09:17:09
Uptime                    0 days 0 hr. 0 min. 0 sec
Trace Level               off
Security                  ON: Local OS Authentication
SNMP                      OFF
Listener Parameter File   /u01/app/gateway/network/admin/listener.ora
Listener Log File         /u01/app/gateway/diag/tnslsnr/Abbott/listener/alert/log.xml
Listening Endpoints Summary...
  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1523)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.56.100)(PORT=1523)))
Services Summary...
Service "dg4msql" has 1 instance(s).
  Instance "dg4msql", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully

　　监听配置成功，接着就是配置tns，注意：这里的tns需要在oracle的home/network/admin/tnsnames.ora文件中配置：

[oracle@Abbott admin]$ cat tnsnames.ora
# tnsnames.ora Network Configuration File: /u01/app/oracle/product/11.2.0/db_1/network/admin/tnsnames.ora
# Generated by Oracle configuration tools.

MSDB =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST =192.168.56.100)(PORT = 1523))
    (CONNECT_DATA=(SID=dg4msql))
    (HS=OK)
  )

　　配置完成后尝试tnsping：

[oracle@Abbott admin]$ tnsping MSDB

TNS Ping Utility for Linux: Version 11.2.0.4.0 - Production on 04-JUL-2017 11:30:13

Copyright (c) 1997, 2013, Oracle.  All rights reserved.

Used parameter files:

Used TNSNAMES adapter to resolve the alias
Attempting to contact (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST =192.168.56.100)(PORT = 1523)) (CONNECT_DATA=(SID=dg4msql)) (HS=OK))
OK (0 msec)

　　如果tnsping没有问题，接着就可以进入数据库，创建dblink，然后查询mssqlserver的数据：

SQL> create public database link aaaa connect to "sa" identified by "1qaz@WSX" using 'MSDB';

Database link created.

SQL>  select * from dbo.t1@AAAA;

        id
----------
         1

SQL> /

        id
----------
         1

在表t1中再插入一行数据：

SQL> /

        id
----------
         1
         2

　　

遇到问题：

SQL> select 1 from dual@aaaa;
select 1 from dual@aaaa
                   *
ERROR at line 1:
ORA-28513: internal error in heterogeneous remote agent
ORA-02063: preceding line from AAAA

　　最后检查，时因为监听中的SID_NAME错误的指定成了MSSQLSERVER的数据库名称MSDB，而不是dg4msql，这里为什么要指定为dg4msql呢？因为gateway的参数文件格式为initSID.ora，而默认的SID为dg4msql，我们也没有人为改动，指定SID表明gateway具体监听的哪个数据库，而当指定了dg4msql时，它自动会寻找initdg4msql.ora这个文件，从而根据配置文件找到对应的MSSQLSERVER。