Configure macOS Catalina to connect to Oracle DB using RStudio and odbc library
This example demonstrates how to connect RStudio on macOS Catalina to an Oracle database using the odbc and DBI libraries. It shows the complete setup process, including installing unixODBC via Homebrew, downloading Oracle Instant Client files, configuring environment variables in `.bash_profile`, and editing the `odbc.ini` file to define the data source. The code uses `DBI::dbConnect()` with the `odbc::odbc()` driver to establish the connection and a SQL query `select sysdate from dual` to verify the setup.