It is very easy for PHP to connect to oracle8 under Linux/Unix, but it is really not easy under the windows platform. I have found a reliable method after a long period of exploration. I dare not keep it to myself, so I am publishing it for everyone. The development environment used by the author: windows 98 second edition php4.04pl1 apache 1.3.14 window version oracle 8.05 client After PHP is installed in CGI mode and tested successfully. Use the following code to test About the connection parameter issue: The connection string is set to the following: (DESCRIPTION =(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.3.202)(PORT = 1521))(CONNECT_DATA = (SID = unicom) )) PROTOCOL: for the network protocol used HOST: for the host name of the database server SID: for the instance number of the database There is generally no problem after doing this. If your Oracle 8 client is 8.1.6i Enterprise Edition, you can set these parameters in the connection string and use the Net Easy Config utility of Oracle8 to set them. Pass the set connection string name as the connection string. It is speculated that this method can also be used in Oracle 7.x. Since there is no environment, it has not been tested. If you are interested, you can try it.