Revisiting databases

Before we dive deep into LDVs and some associated topics, let's take a brief history trip. Understanding relational and non-relational databases will help us understand the different types of solutions that are available with Salesforce and assist us in determining which one to use depending on requirements. In the early days of modern computing, tapes were used for storage, and the first digital-tape storage system, IBM's Model 726, could store 1.1 MB (megabytes) on a single reel of data. For comparison purposes, these days, a tape cartridge can hold up to 15 terabytes (TB). Model 726 was a non-relational database in that it was free-form records linked together.

Then came relational databases, which offered a more organized approach to store, retrieve, and search data. Data was stored in multiple tables in keeping with normalization principles and logically linked together using unique identifiers called primary and foreign keys. Refer to Chapter...