Active Record operations
Active Record is a design pattern created to simplify communication with the DB. Historically, SQL is a standard for communicating with most databases. However, each database has adopted its own unique set of SQL commands and standards. While they are all very similar, each one has its own peculiarities, in part because not all databases have the same set of features. A great article detailing some of the concepts regarding the Active Record design pattern is this one:
https://blog.savetchuk.com/overview-of-the-active-record-pattern
As an example, PostgreSQL offers a more sophisticated set of data types than MySQL. Another example is SQLite in web applications, which is very easy to set up, but does not work well in large applications. In Rails, SQLite is mostly used for quick setups and development. Where does Active Record come into the picture? Active Record uses a technique called Object Relational Mapper (ORM). This technique involves “mapping...