Persisting information with database systems
Our prediction service will use data in a number of ways. When we start the service, we have standard configurations we would like to retrieve (for example, the model parameters), and we might also like to log records of the requests that the application responds to for debugging purposes. As we score data or prepare trained models, we would ideally like to store these somewhere in case the prediction service needs to be restarted. Finally, as we will discuss in more detail, a database can allow us to keep track of application state (such as which tasks are in progress). For all these uses, a number of database systems can be applied.
Databases are generally categorized into two groups: relational and non-relational. Relational databases are probably familiar to you, as they are used in most business data warehouses. Data is stored in the form of tables, often with facts (such as purchases or search events) containing columns (such as user account...
