DA0-001 CompTIA Data+ Certification Exam Free Practice Exam Questions (2025 Updated)

Aline chartis the best visualization for displaying data trends over time. It clearly shows changes and trends in the data by connecting data points with lines, making it ideal for representing time-series data such as quarterly sales.

CompTIA Data+ Reference:

CompTIA Data+ Study Guide (Exam DA0-001), Chapter 7: Data Visualization and Reporting, Section “Choosing the Right Visualization for Time-Based Data”, Official CompTIA CertMaster Learn for Data+, Module 7.1 “Time-Series Visualization: Line Charts”.

A discrete data type is a data type that can only take on a finite number of values, such as integers or categories. An example of a discrete data type is the number of kids, as it can only be a whole number. The other options are examples of continuous data types, as they can take on any value within a range. The length in inches or centimeters, the distance in miles or kilometers, and the weight in pounds or kilograms are all continuous data types. Reference: CompTIA Data+ (DA0-001) Practice Certification Exams | Udemy

Merging tables to create a master file that includes all transactions for both online and in-store sales is best described as data consolidation. This process involves combining data from various sources into a single, unified dataset. Data consolidation is essential for providing a comprehensive view of all transactions, which can be used for analysis, reporting, and decision-making purposes.

 Scheduled report delivery is a feature that allows a data analyst to automate the generation and distribution of a report at a specified time and frequency. This would be the best method to ensure that the sales managers receive the weekly report on sales performance without manual intervention. Subscription access delivery is a feature that allows users to subscribe to a report and access it on demand, but it does not automate the delivery. Printing out a copy or uploading the report to the server are manual methods that require more time and effort from the data analyst. Reference: CertMaster Practice for Data+ Exam Prep - CompTIA

The ‘Status’ column in the dataset shows different terms such as “yes”, “completed”, “done”, and “Y” that likely represent the same outcome - that a task has been completed. This variation in terms leads to inconsistency within the data. Data profiling aims to ensure that data is consistent, among other quality metrics, to facilitate accurate analysis and reporting. By recoding the ‘Status’ column, the analyst seeks to address this inconsistency, ensuring that all entries indicating completion are represented uniformly. This enhances the data quality and usability for subsequent data analysis tasks.References:

The action of recoding is taken to standardize the data entries and eliminate inconsistencies, which is crucial for maintaining data integrity and ensuring reliable data analysis.

Themean(average) is the most sensitive measure when it comes to outliers. If a dataset contains extreme values (either very high or very low), theydisproportionately affect the mean, making it a less robust measure of central tendency​.

The rating variable in a survey where participants rate a company on a scale of one to ten is best described as ordinal. This is because the ratings are ranked in order, with each number representing a position on a scale of satisfaction or quality. The numbers are not just labels (which would be nominal), nor do they represent a continuous spectrum (which would be continuous). They also do not fit the definition of categorical, as that implies non-ordered groups or categories. In an ordinal scale, the order of the values is significant and meaningful12.

Explanation

Correct answer C. Snowflake.

Since the dimension links to a dimension that isn't connected to the fact table, it must be a Snowflake, with a Star, all dimensions link directly to the fact table, Sun and Comet are not data warehouse design patterns.

Explanation

Normalization is the process of reorganizing data in a database so that it meets two basic requirements: There is no redundancy of data, all data is stored in only one place. Data dependencies are logical, all related data items are stored together.

Put simply, data normalization ensures that your data looks, reads, and can be utilized the same way across all of the records in your customer database. This is done by standardizing the formats of specific fields and records within your customer database.

A data dictionary is a collection of metadata that describes the data elements in a database or dataset. It can help improve data acquisition by providing information about the data sources, formats, quality, and usage. It can also help remember specifics about data fields, such as their names, definitions, types, sizes, and relationships. Therefore, options B and D are correct.

Option A is incorrect because it is not a reason to create and maintain a data dictionary, but a benefit of doing so.

Option C is incorrect because specifying user groups for databases is not a function of a data dictionary, but a function of a database management system or a security policy.

Option E is incorrect because confining breaches of PHI data is not a function of a data dictionary, but a function of a data protection or encryption system.

Option F is incorrect because reducing processing power requirements is not a function of a data dictionary, but a function of a data compression or optimization system.

A credit card number is an example of structured data, which is a type of data that conforms to a data model, has a well-defined structure, follows a consistent order, and can be easily accessed and used by a person or a computer program. A credit card number consists of 16 digits that are divided into four groups of four digits each, separated by spaces or hyphens. The first six digits indicate the issuer identification number, the next nine digits indicate the account number, and the last digit is a check digit that validates the number. A credit card number can be stored and processed in a structured format, such as a database or a spreadsheet1.

The "Age" field contains values in different formats (e.g., "30", "65F", "24"). This indicates aconsistency issuesince data in the same column should adhere to the same format (age as a number only). Mixing formats creates confusion and errors during analysis.

CompTIA Data+ Reference:

CompTIA Data+ Study Guide (Exam DA0-001), Chapter 5: Data Cleaning and Preparation, Section “Ensuring Data Consistency”, Official CompTIA CertMaster Learn for Data+, Module 5.2 “Common Data Quality Issues: Consistency”.

References Used:

CompTIA Data+ Study Guide (Exam DA0-001) – Official Sybex/CompTIA Book

CompTIA CertMaster Learn for Data+ – Official CompTIA Learning Modules

CompTIA Data+ Objectives (DA0-001)

Unsupervised data mining techniques are used to identify hidden patterns or intrinsic structures in data without prior labels or classifications. Among the options provided,clusteringis a primary unsupervised learning method.

Option A:Clustering

Rationale:Clustering involves grouping a set of objects in such a way that objects in the same group (or cluster) are more similar to each other than to those in other groups. This technique is unsupervised because it doesn't rely on predefined labels and is used to discover natural groupings within data.

 A dashboard is a graphical display that summarizes and presents key performance indicators (KPIs) and metrics for a business or a project. A dashboard should be clear, concise, and easy to understand. To develop a dashboard, one of the best practices is to create a wireframe or a mockup first. A wireframe or a mockup is a low-fidelity sketch or prototype of the dashboard layout and design, which helps to define the scope, requirements, and functionality of the dashboard. Creating a wireframe or a mockup can help to save time and resources, as well as to get feedback from stakeholders and users before deploying the dashboard to production. Therefore, the correct answer is A. References: [Dashboard Design Best Practices: 4 Key Principles | Toptal], [How to Create an Effective Dashboard (with Examples) | Tableau]

The correct answer is B. Recoding.

Recoding is a data manipulation technique that involves changing the values or categories of a variable to make it more suitable for analysis.Recoding can be used to simplify or group the data, to correct errors or inconsistencies, or to create new variables from existing ones12

In the example, the analyst used recoding to change the values of Var001, Var002, Var003, and Var004 from numerical to textual form. The analyst also used recoding to assign meaningful labels to the values, such as “Absent” for 0, “Present” for 1, “Low” for 2, “Medium” for 3, and “High” for 4. This makes the data more understandable and easier to analyze.

Astar schemahas a central fact table linked to multiple dimension tables. The dimension tables are typically denormalized, meaning data is stored in a flat, non-normalized format for faster query performance. This design enables efficient queries in data warehousing and business intelligence.

CompTIA Data+ Reference:

CompTIA Data+ Study Guide (Exam DA0-001), Chapter 3: Databases and Data Sources, Section “Star Schema Design and Usage”, Official CompTIA CertMaster Learn for Data+, Module 3.6 “Data Warehousing Schemas”.

References Used:

CompTIA Data+ Study Guide (Exam DA0-001) – Official Sybex/CompTIA Book

CompTIA CertMaster Learn for Data+ – Official CompTIA Learning Modules

CompTIA Data+ Objectives (DA0-001)