Objective 1.0 Database Fundamentals Of Relational Database

?? Good afternoon. Today I hope we are all having a great day and beginning to start the New Year well. Today we will cover Objective 1.0 of the CompTIA Data system + certificate exam. For this lesson, we will start covering objective 1.0 on the difference between relational and nonrelational databases. Every day and week, we will cover objectives on the Data Systems + certification exam before it is released next summer! I took the beta exam and believed we could prepare for this exam once it gets released in the summer. This examination will focus on database administration & database engineering terminology! So let us get ready and rock this examination.

• Objective 1.1 Compare and contrast database structure types

Relational Databases

?? Relational Databases are commonly used today, but what is a relational database, and how does it work? Let us break down a few examples of a relational database! Whenever we make transactions, our data is stored in columns, so if you purchase one tomato at the grocery store, The data will be held in the groceryfood_name column. The price of tomato will be inside its separate column as well, and we will call this column grocery_price. The table that will store this data is called the grocery food table.?

?? This is a perfect example of how relational database schema looks. We must understand that each column inside the grocery food table has a unique key assigned to them. Later this will become important when individual columns need to be identified inside the database table and when we want to combine tables.

? Important: Unique key or ID is assigned to each column and is used to create relationships for tables.

?? Relational databases follow rules that allow them to have strong foundations of integrity, for example, when creating a column in a database table. We will not be permitted to name the column the same as other columns inside the database. This rule is an example of relational database model integrity.?Our columns must have different unique identifiers if they are inside the same table. Remembering this will be important if we are questioned about how database integrity is managed in Relational Database.

Relational Database Model & ACID Model

The relational database model simplifies how data structures and data are stored by using simplified table architecture that allows much more flexibility and efficiency in querying designs and pulling data. When transaction or data is manipulated or changed, relational databases do an excellent job of showing us instant change in data, such as verifying the video game score when the player instantly makes the play and scores a point or even making banking transaction and seeing the real-time change in data. Social media as well such as Facebook, Twitter & Instagram use Relational database that allows us to see instant transaction in new followers or likes on post.

?? The point or new follower will reflect instantly if being stored with a relational database model. Refer to the bottom example below for the ACID model. This will become important when taking the CompTia Data Systems + examination. We will discuss this model later in future articles, but I want to expose ourselves to the ACID model.

• Atomicity: Describes all the elements that are required to complete database transaction.
• Consistency: Defines the rules for maintaining all data points in correct state after a transaction.
• Isolation: Keeps the event of the transaction invisible to others until it its fully committed to avoid confusion.
• Durability: Ensures database changes become permanent once the transaction is complete.

? Important: For the CompTIA Data Systems + exam, ensure that you are comfortable in understanding the ACID principles as for sure expect questions on the exam to cover ACID principles.?

How Do We Remember What Relational Database?

The relational database we can best remember as a database structure that uses columns and unique IDs & Primary keys that allow us to link database tables together and create a relationship with another database table. When we think of relational database, I want us to remember how bank transaction is performed or how the score chart is consistently updated. These updates and transactions are precisely how a relational database works when updating data and information, it instantly reflects, allowing us to see the real-time transaction being performed.?

Instagram, Facebook & Twitter allow users to like photos. When we instantly like a picture, the transaction and column in a database table that tracks all follower's likes will immediately update, reflecting on the application for the viewer to see. These are great examples of how relational database works and functions in infrastructure are essential to understand.

Conclusion

For today's article, we covered some important topics we will see during our CompTia Data Systems + exam. I will be making flashcards concerning all critical points that we need to remember to succeed during the exam when it's released in the summer of 2023. As we move to the next part of Objective 1.0 Data Systems + examination, I want us to review everything to the best of our ability. I look forward to our next article discussing our next part, Objective 1.0 of the CompTia Data Systems + examination.?