Oracle Patching

Install Oracle Instant Client

Install the current Microsoft VS Redistributable

   https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads

Download the latest version of the Oracle Instant Client

   https://www.oracle.com/database/technologies/instant-client/downloads.html
   You'll want to download both the basic and sdk packages for your system arch.

Extract both packages

   Copy the SDK directory from the SDK package and paste it into the other instantclient_XX_X directory

Copy the instantclient directory to

   D:/oracle/instantclient_XX_X

Update Env Vars

   Click on the Windows Icon and type environment variables.
   click on "Edit the system environment variables".

Add Variable

   Under the System Variables, click New...
   Enter the variable name OCI_LIB64
   And the value: D:/oracle/instantclient_XX_X
   Click OK, close those windows.

Install SQLplus Utility

Download the latest SQL*Plus Package

   https://www.oracle.com/database/technologies/instant-client/winx64-64-downloads.html

Unzip and Install

   Unzip the package, copy the contents of the zipped folder and place them in D:/oracle/instantclient_XX_X.
   Why Oracle has these all separate instead of just one package that you need is beyond me.

Connect to the Database

Pop open a terminal (I've been using as Admin) and type

   sqlplus user/password@CARDS
   EX: sqlplus cwf/password@CARDS
   I assume if no password is provided it'll prompt, which is safer. 
   We'll need sqlplus later to turn off the database. Opatch won't apply the patch otherwise.

Download the latest Opatch

   https://support.oracle.com/knowledge/Oracle%20Database%20Products/274526_1.html