I am sure changefeed does not require any introduction now. We have already used or discussed it in almost every chapter. In this section, we are going to learn why RethinkDB can act as a Polyglot agent.
As I have mentioned in the previous section, synchronizing various kinds of databases requires the following two important things:
An event to trigger the process
Database-specific listeners
Any time we add/update/delete the data in our entry database, an event must be triggered in order to start the process of synchronization. Then we need a database-specific listener who in turn performs the data manipulation in the respective databases.
So to trigger an event, we need to first know that there is some kind of change happening in the database. You can do this easily by writing an extra piece of code if the program which is doing the manipulation in the database is written or controlled by you. However, if the manipulation is done by the various...