Especificar un cliente de Oracle alternativo al abrir ArcMap

Resumen

Users with multiple 32-bit Oracle client versions installed on their machines need to make certain that the path to the proper client is listed first in their PATH variable to successfully connect to the database. If there are other non-Esri programs on the machine that have this same requirement, the PATH variable must be changed to accommodate that software's requirements and then changed back to allow Esri software to successfully connect.

Causa

When a connection to an Oracle database is initiated with ArcMap, the Esri libraries attempt make a call to Oracle's Call Interface (OCI) function to create the connection by loading the Oracle Client library. The library it loads is the first client that it finds within the PATH variable. If the required client version is not the first one found, this can result in an error.

Procedimiento

In situations where the PATH environmental variable must be changed temporarily to accommodate opening ArcMap, the following workaround can be implemented.

1. Create a batch script which sets the PATH to the proper Oracle client as well as to the bin folder of the ArcMap installation you are launching. Follow this up with a START ArcMap.exe command and exit.
   For example:

SET path=C:\Oracle\Ora11g\bin;C:\Program Files (x86)\ArcGIS\Desktop10.3\bin;

START ArcMap.exe

exit

2. Update the string "C:\Oracle\Ora11g\bin;C:\Program Files (x86)\ArcGIS\Desktop10.3\bin;" in the above script to match the proper locations on your machine, and save the script as a batch file (.bat). 
3. Browse to the location of the batch file and double-click it to run it.

Running this script temporarily sets the PATH environmental variable to point to the alternate Oracle client and open ArcMap.  These environmental variables only persist for the ArcMap session and do not change the variables for any other programs being opened with their launchers. If another ArcMap session is opened without the batch file, the default PATH variables are used.