ORM stands for object-relational mapping and is a very important technique in application development, especially for those applications that interact with databases. Traditionally, to store or retrieve data from the database, you need to write SQL, which stands for the structured query language. After executing an SQL query, you get back a table full of data that needs to be mapped to objects of a certain class, to make it easy to interact with the raw data that is returned from the database.
For example, if we have a table full of Shopping Lists, then it would be good if we got back an array of objects of the type ShoppingList, instead of an array of dictionary objects containing column names and column value key pairs. Using a mapping technique, we can convert this raw data stored in the database into an object of a certain type...