Connect oracle database link to mssql

Oracle database link connects to different database platforms in mssql, which is generally called a heterogeneous database service. Different vendors have different implementation technologies: in SQL SERVER, it is called a LINKED SERVER, use ODBC to interconnect with other databases. The technology for implementing heterogeneous services in ORACLE is called Transparent Gateway ). Currently, ORACLE uses transparent gateways to connect with SQL SERVER, SYBASE, DB2, and other databases. The Oracle transparent gateway software needs to be purchased separately for Oracle 8i at about $10 thousand. It was released as a database component for free at Oracle 9i. Select the component type during installation. (It is not installed by default .) Step 1: Install the oracle component Transparent Gateway; select "Custom" in the installation type; select "oracle Transparent Gateway for Microsoft SQL server" on the components page; Step 2: after installing the transparent gateway for SQL server software, you can view the tg4msql directory under $ ORACLE_HOME and edit $ ORACLE_HOME/tg4msql/admin/inittg4msql. there is a row in the SQL file: HS_FDS_CONNECT_INFO = "SERVER = 192.168.1.46; DATABASE = pubs" where: SERVER = 192.168.1.46 is the name of the SQL SERVER and the DATABASE is the name of the DATABASE. Step 3: Modify the listener in the D: \ oracle \ ora92 \ network \ admin path. add the following to the SID_LIST file: (SID_DESC = (SID_NAME = tg4msql) -- you can name it yourself (ORACLE_HOME = d: \ oracle \ ora92) (PROGRAM = tg4msql) Step 4: modify tnsnames in the d: \ oracle \ ora92 \ network \ admin path. add the following to the ora file: mssql = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP) (HOST = 192.168.1.46) (PORT = 1521 ))) (CONNECT_DATA = (SID = tg4msql) (HS = OK) Step 5: Create a database link in oracle; Log On With dba in sqlplus; create database link mssql connect to sa identified by password using 'mssql'; then select * from tablename @ mssql; can be used to access the mssql database!