PHP and Oracle: Christopher Jones

The common problem with using IIS, PHP and Oracle is incorrect permissions.

The Problem

Your Windows machine has IIS, PHP and Oracle. You create a PHP script using the oci8 extension and it calls PHP5 functions like oci_connect(), oci_parse(), or PHP4 functions like OCILogon() and OCIParse(). You invoke the script and get errors like:

"Warning: ocilogon() [function.ocilogon]: OCIEnvInit() failed."

"Unable to load dynamic library php_oci8.dll - Access is denied"

The Cause

As Monty wrote in the OTN Forum

If the IIS is allowed to use the anonymous logon it uses IUSR_<machinename> account to read the files, therefore this user needs to have read access on oracle installation directory.

The Solution

1. Install your Oracle client

2. The inet-user needs now access rights for the

   • oracle folder
   • oracle\bin folder
   • tnsnames.ora file - if you are using a net alias in oci_connect()  as your database name in PHP.  A net alias is a text string like "PROD1" or "XE" that is defined in a tnsnames.ora file.
   
   Christian Wenz has a tip in the not-a-bug PHP bug 29835  that
   
   

   IUSR_MACHINENAME needs read access to the _complete_ bin directory (be sure to check the "replace permissions" options when setting this).

   You might want to use a dependency checker to verify exactly what access is needed.
   

3. Set these Environment Variables in Control Panel -> System -> Advanced -> Environment Variables

   • ORACLE_HOME = "C:\oracle\ora92"
   • NLS_LANG if you use a non default (non-American) language or character set
   • TNS_ADMIN if you are using your own tnsnames.ora instead of the default ORACLE_HOME\network\admin\tnsnames.ora. Set TNS_ADMIN to the directory containing tnsnames.ora; it is not set to the file name.

4. Restart IIS

   A posting by Andy Hassall
   says "IIS runs as a child of the IIS Admin service. This then runs as a
   child of SERVICES.EXE. Processes inherit environment from their parent.
   Since you can't really stop SERVICES.EXE without the system going tits
   up, changing the environment seen by IIS without a reboot appears
   tricky, as changing the environment for your command prompt or the
   system has no effect on other already-running processes."