Recap of RDBMS Concepts

Let us recap some of the RDBMS concepts before performing CRUD Operations. We will develop programs to interact with Database using Postgres which is RDBMS Database.

  • RDBMS stands for Relational Database Management System.

  • Tables will be normalized to ensure that records are uniquely identifiable, related with each other, etc.

  • Most of the database tables supporting transactional applications are either in 3rd Normal Form or Boyce Codd Normal Form.

  • There are different types of relationships between tables.

    • one to one

    • one to many

    • many to one

    • many to many (typically implemented via bridge tables)

  • Tables typically contain different type of constraints.

    • Primary Key Constraints

    • Unique Key Constraints

    • Not Null Constraints

    • Foreign Key Constraints referencing Primary Key Constraints of its parent table.

    • and more

  • Data Model for Cloudera’s Sample Retail Database. image.png