Encounter this problem, online search a lot, most of the inaccurate interpretation, after exploring according to their own understanding to write how to solve.
Phenomenon: The problem is more clear on the Internet, the use of Plsql Developer connection to the database will report a problem with the inability to locate the Oci.dll file, there may be different reports, but the problem is to say this file problem.
Cause: The Plsql Developer used here is 32 bits, and the database is 64 bits, so plsql Developer cannot use the 64-bit Oci.dll Library of the database.
Workaround: Install a 32-bit database client, and then search for the location of the Oci.dll file in it, and then write down the location. Open the Plsql Developer software and click Cancel to enter the interface. Tools--Preferences open preferences.
Then make sure to save and then restart Plsql Developer on it. Finally, the previous problem is resolved before and after the landing interface changes in the comparison chart.
When it comes to mapping-related development, the tools also require 32-bit clients for configuration, which should be similar.
32-bit Plsql Developer Oracle database problem handling with no 64-bit connectivity