Book Image

CompTIA Data+: DAO-001 Certification Guide

By : Cameron Dodd
Book Image

CompTIA Data+: DAO-001 Certification Guide

By: Cameron Dodd

Overview of this book

The CompTIA Data+ certification exam not only helps validate a skill set required to enter one of the fastest-growing fields in the world, but also is starting to standardize the language and concepts within the field. However, there’s a lot of conflicting information and a lack of existing resources about the topics covered in this exam, and even professionals working in data analytics may need a study guide to help them pass on their first attempt. The CompTIA Data + (DAO-001) Certification Guide will give you a solid understanding of how to prepare, analyze, and report data for better insights. You’ll get an introduction to Data+ certification exam format to begin with, and then quickly dive into preparing data. You'll learn about collecting, cleaning, and processing data along with data wrangling and manipulation. As you progress, you’ll cover data analysis topics such as types of analysis, common techniques, hypothesis techniques, and statistical analysis, before tackling data reporting, common visualizations, and data governance. All the knowledge you've gained throughout the book will be tested with the mock tests that appear in the final chapters. By the end of this book, you’ll be ready to pass the Data+ exam with confidence and take the next step in your career.
Table of Contents (24 chapters)
Part 1: Preparing Data
Part 2: Analyzing Data
Part 3: Reporting Data
Part 4: Mock Exams

Handling entity relationship requirements

Entity relationship requirements are sometimes laws, but more often, rules about how pieces of data can relate to one another. An entity is a table, model, or data object. Entity relationships are how these data objects connect to each other. You can see how this happens in an entity relationship diagram, as shown in Figure 14.1:

Figure 14.1 – Entity relationship diagram

Figure 14.1 – Entity relationship diagram

This looks a lot like a flowchart and shows not only that the tables are connected, but often the specific variables that connect them, and the markings on the line can denote what kind of relationship these variables have. Again, you will need to look up what the entity relationship requirements are for you, but there are a few main types of requirements:

  • Record link restrictions
  • Data constraints
  • Cardinality

Let’s go ahead and look at these in a little more detail.

Record linkage, or data linkage, is, as...