You prepare for Oracle Call Interface (OCI), ODBC, and JDBC OCI connections by downloading and installing Oracle Instant Client and then downloading the client credentials for your Autonomous Database and making them available to Oracle Instant Client.

1. Download and install the Oracle Instant Client basic package for your system's OS and architecture:

   • Oracle Linux:

     1. Enable the Instant Client channel:

        yum -y install oracle-release-el7

     2. Download and install the Instant Client 19.3 basic package:

        yum -y install oracle-instantclient19.3-basic

   • Other OSes and architectures:

     1. Go to the Oracle Instant Client Downloads page and select the download for your system's OS and architecture.

     2. On the download page, accept the Oracle Technology Network License Agreement, download the latest version of the Basic Package, and then install it by following the instructions at the bottom of the download page.

2. Download the zip file containing client credentials for your database to a secure directory on your computer.

   This zip file is available for download from the database's Details page in the Oracle Cloud console. See Download Client Credentials for information on downloading client credentials for Autonomous Database.

3. After downloading the zip file, follow these steps:

   1. Unzip the client credentials zip file.

   2. Edit the sqlnet.ora file provided in the client credentials, replacing "?/network/admin" with the full path of the directory where you unzipped the client credentials; for example, change:

      (DIRECTORY="?/network/admin")

      to:

      (DIRECTORY="/users/jdoe/adbcredentials")

   3. Create the TNS_ADMIN environment variable, setting its value to the full path of the directory where you unzipped the client credentials.