What is a Database System?

This is a simple note on what is the database system.

From a high level, the database is an organized collection of structured data that is typically stored electronically in a storage medium.

Application developers suppose to write software to handle and maintain the data in the storage medium. This is hard and makes the application developers' job extremely hard. For instance, data integrity and durability, etc. However, the database system research abstracts all low-level components and helps application developers to focus on applications logics by developing database management systems.

Database management system(DBMS ) manages the data in the storage devices. The below figure gives an overview of database systems. Examples of database systems are DBase, MYSQL, and MongoDB.

The data model is defined as how related data are connected to each other and are stored in the database. It defined how to represent data in the storage.

types: Hierarchical model, Network model, Entity-Relationship model, and Relational model

The most used one is a relational model where the data is stored in form of tables. The database management system for the relational model is called a relational database management system (RDBMS). An example of a database system is called MYSQL. SQL is a programming language for RDMS software.

DBMS Schema: is a structure of the database.

DBMS instance: the state of the stored value.

End of the what is the database.

The next post is an introduction to the Cockroach database.