In order for this app to work you need installed and configured MariaDB on your computer and a creds.R file with structure displayed below in your working directory.
con <- dbConnect(RMariaDB::MariaDB(),
username = "user",
dbname = "database",
password = "password",
host = "00.000.000.00")
Current structure of the database is displayed below.
Plot was made in MySQL Workbench 6.3 CE.