Oracle Instant Client Devel is a free devel headers
for connecting to Oracle databases.
It provides additional header files for compiling
applications against instantclient.
Oracle-xe and JRE or JDK packages are optional and
depends on your needs.
You need an Oracle account and you must Agree to Oracle's
download agreement before this can be downloaded.
You have to use a web browser to download it.
Ensure that you download the correct RPM
"Instant Client Package - SDK"
For x86: oracle-instantclient12.1-devel-12.1.0.2.0-1.i386.rpm
For x86_64: oracle-instantclient12.1-devel-12.1.0.2.0-1.x86_64.rpm