For usage instruction see commandref.html, section define of DbLog

- db.conf
  sample database configuration file
- db_create_mysql.sql
  sample sql command to create a MySQL or MariaDB database for logging purposes
- db_create_postgresql.sql
  sample sql command to create a PostgreSQL database for logging purposes
- db_create_sqlite.sql
  sample sql command to create a SQLite database for logging purposes
- fhemdb_get.pl
  short sample perl script for retrieving the current (latest) data from
  the logging database