DA0-002 · domain
Data Concepts and Environments
Practise CompTIA Data+ (DA0-002) Data Concepts and Environments practice questions — original exam-style scenarios with answer choices, explanations, and analysis of common mistakes.
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Data Concepts and Environments questions test whether you can apply the concept in context, not just recognise a definition.
How the topic appears in realistic exam-style scenarios.
Which detail in the question changes the correct answer.
How to eliminate plausible but wrong options.
How to connect the question back to the wider exam objective.
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Common Data Concepts and Environments exam traps
- ▸Answering from memory before reading the full scenario.
- ▸Missing a constraint such as cost, availability, security, scope or command context.
- ▸Choosing a broad answer when the question asks for the most specific fix.
- ▸Ignoring why the wrong options are tempting.
Question index
All Data Concepts and Environments questions (186)
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A healthcare provider needs to integrate patient data from multiple clinics into a single data warehouse. Which process is used to extract, transform, and load the data?
Easy2A retail company wants to analyze customer purchase patterns over time. The data is stored in a relational database with tables for Customers, Orders, and Products. Which database concept should be used to ensure that each order references a valid customer?
Medium3A healthcare organization is subject to strict data privacy regulations requiring the classification of all data assets. The data governance team has identified three data sensitivity levels: Public, Internal, and Restricted. They have a new data pipeline importing patient health records from multiple clinics. The records include patient names, diagnoses, treatment codes, and insurance information. The team must ensure that the classification is applied correctly and that restricted data (e.g., diagnoses) is not exposed to unauthorized personnel. However, the pipeline uses automated tagging based on metadata rules, and some fields are misclassified. What is the most effective immediate action to improve classification accuracy?
Hard4Which TWO of the following are benefits of database normalization to 3NF? (Select 2)
Medium5A data analyst needs to combine customer data from two tables: Customers (CustomerID, Name) and Orders (OrderID, CustomerID, Amount). Only customers who have placed at least one order should be included. Which JOIN type should be used?
Hard6A data analyst is working with a dataset that includes customer names, email addresses, and purchase history. The analyst wants to ensure that each customer is uniquely identified. Which TWO database concepts should be used to enforce uniqueness and link related data?
Easy7Match each data quality dimension to its description.
Medium8A data analyst notices that a column labeled 'Income' contains values like '$50,000' and '$75,000', but also 'High' and 'Low'. What data concept issue is occurring?
Hard9A company needs to store user session data for a web application. Each session has a unique session ID, and the data must be retrieved very quickly by session ID. The data does not require complex relationships or transactions. Which type of NoSQL database is most appropriate?
Hard10A marketing team needs to store customer feedback from social media posts, including text, images, and emojis. Which data concept is most appropriate for this storage?
Easy11A data engineer is designing a data pipeline for a retail company. The source system is an OLTP database that records sales transactions. The target is a data warehouse used for reporting. The engineer is evaluating whether to use ETL or ELT. Which three factors would favor using ELT over ETL? (Select THREE)
Hard12A company uses a NoSQL document database to store product catalogs. Each product document includes fields like product_id, name, category, and price. The operations team frequently queries by product_id and by category. Which type of NoSQL database is being used, and what should be created to optimize queries by category?
Hard13Which TWO of the following are characteristics of structured data? (Choose TWO.)
Easy14Which of the following is a characteristic of a NoSQL document database like MongoDB?
Easy15To consolidate data from multiple operational databases into a central repository for reporting, a company decides to transform data before loading it into the target system. Which data integration approach is being used?
Medium16Which THREE of the following are NoSQL database types?
Hard17A healthcare analytics team is building a dashboard to monitor patient vitals. They receive data from two sources: Source 1 provides 'heart rate' as an integer (beats per minute), and Source 2 provides 'blood pressure' as a ratio (systolic/diastolic, e.g., 120/80). The team wants to create a combined metric called 'cardiac stress index' that uses both heart rate and systolic blood pressure. However, they notice that heart rate data occasionally contains negative values due to sensor errors. The data governance policy requires that all data be valid and meaningful. Which action best addresses the data quality issue while preserving the data types?
Medium18A retail analyst needs to determine the most popular product category. The dataset includes columns: ProductID, Category, SalesDate, QuantitySold, UnitPrice. Which column contains qualitative data?
Easy19A data engineer is designing a system to store raw sensor data from thousands of IoT devices. The data is expected to be used for exploratory analytics and machine learning. Which storage solution is most appropriate?
Medium20A data architect is designing a schema for a product catalog where each product has a variable number of attributes. Which NoSQL database type is most appropriate?
Easy21A database has a table 'Orders' with columns OrderID (PK), CustomerID, OrderDate, and a table 'OrderDetails' with OrderID (FK), ProductID, Quantity. To ensure that every OrderID in OrderDetails exists in Orders, which integrity constraint is enforced?
Hard22An organization uses a data warehouse for analytics. Which two characteristics are typical of a data warehouse compared to a data lake? (Select TWO.)
Hard23A company's database has a table 'orders' with columns: order_id, customer_id, order_date, and total_amount. A data analyst needs to identify customers who have placed more than 5 orders in the past year. Which data concept should be used to group orders by customer and count them?
Medium24A data analyst needs to retrieve current weather data from a third-party service. The service provides an endpoint that returns data in JSON format over HTTP. Which data source type is being used?
Medium25A data analyst needs to extract data from a transactional database and load it into a data warehouse for reporting. Which process typically transforms the data before loading it into the warehouse?
Medium26A company needs to store raw data from IoT sensors for future machine learning projects. The data is expected to be massive and in various formats. Which storage solution is most appropriate?
Medium27A data warehouse team is considering moving from an ETL to an ELT approach. Which THREE of the following are advantages of ELT over ETL?
Hard28A data analyst is comparing characteristics of structured and unstructured data. Which TWO of the following are characteristics of structured data? (Choose two.)
Medium29Match each data visualization type to its best use case.
Medium30A data scientist is building a model to predict customer churn. The company's internal CRM system provides customer demographics and transaction history. They also purchase demographic data from a third-party vendor. How should the purchased data be classified?
Medium31A data engineer is designing a data pipeline where raw data is loaded into a cloud data warehouse (Snowflake) and then transformed using SQL. This approach is called:
Hard32Which THREE data quality dimensions are commonly assessed in a data profiling task?
Hard33Which TWO of the following are considered structured data?
Medium34A data engineer is designing a data warehouse for a retail company. The fact table must record each sale transaction, including product ID, store ID, date, and quantity sold. The product details (name, category, price) are stored in a separate table. This design is an example of which data modeling concept?
Medium35An e-commerce company stores customer support emails in a text database, product images in a blob store, and sales transactions in a SQL table. Which data store holds only structured data?
Hard36Which THREE of the following are components of Master Data Management (MDM)? (Select 3)
Medium37Drag and drop the steps to create a data visualization dashboard in the correct order.
Medium38A data analyst needs to combine customer data from a MySQL transactional database with product data from a MongoDB document store to create a unified view for reporting. The analyst uses a SQL query that joins the tables after extracting data from both sources. Which database concept is being applied?
Hard39Which database concept ensures that data in one table corresponds to data in another table, preventing orphan records?
Medium40Refer to the exhibit. Based on the data profiling results, what is a likely data quality issue?
Hard41An organization wants to assign responsibility for data quality and metadata management. Which role is primarily accountable for defining data standards and ensuring data quality across a specific domain?
Easy42Which of the following data sources is most likely to generate streaming data?
Easy43A data analyst receives a dataset with a column 'salary' that contains values like '45,000', '55,000', and '65,000'. The analyst notices that the values are stored as text. Which data concept should be applied to convert the salary column from text to numeric format for analysis?
Easy44A researcher wants to study the effect of a new drug. She collects data directly from clinical trial participants. Later, she compares her findings with historical data from medical journals. Which contrast best describes her data sources?
Medium45A company requires real-time masking of credit card numbers for customer support agents while allowing full access for accountants. Which technique should be implemented?
Medium46A retail company stores customer purchase history in a relational database. The database contains a table 'transactions' with columns: transaction_id, customer_id, product_id, quantity, price, and transaction_date. A data analyst needs to create a report that shows total revenue per customer for the last quarter. Which data concept describes the relationship between customer_id and total revenue?
Medium47A data analyst receives a file with the extension .json. This file contains product information with attributes that vary between records. How should this file be classified?
Easy48An organization is implementing a data warehouse to support business intelligence reporting. The data warehouse must ensure that transactions are processed reliably. Which property guarantees that each transaction is treated as a single, indivisible unit?
Medium49A data governance team is drafting a policy for handling personally identifiable information (PII). According to data governance best practices, which document should define the classification levels and handling procedures?
Hard50A large financial institution is implementing a data governance framework to comply with new regulations requiring strict control over sensitive customer data. The data governance committee has identified several domains, including customer master data, transaction data, and risk assessment data. They need to decide on a master data management (MDM) approach that ensures a single, authoritative source of customer information across all systems. However, the current environment has multiple legacy systems with conflicting customer records. The committee is concerned about downtime and business disruption during the transition. Which MDM approach best balances data consistency with minimal operational impact?
Hard51A retail company stores customer transaction data in a relational database. They want to analyze purchasing patterns over time. Which type of data structure best supports this analysis?
Easy52A data analyst at a marketing agency is working with a dataset containing customer demographics, purchase history, and social media engagement metrics. The agency wants to perform sentiment analysis on unstructured social media comments to identify brand perception. The dataset also includes structured fields like age, income, and purchase amounts. The analyst needs to choose a storage and processing platform that can handle both structured and unstructured data efficiently without requiring extensive schema definition upfront. Which platform should the analyst recommend?
Easy53Which of the following is a characteristic of structured data?
Easy54A company ingests customer clickstream data from its website. The data arrives continuously in JSON format and must be stored for real-time analytics. Which type of data source is being described?
Medium55Refer to the exhibit. A data analyst notices that direct S3 access to files outside the "incoming/" prefix is blocked. Which data governance principle does this policy enforce?
Medium56A data audit reveals that some numbers in the "Revenue" column were manually entered from PDF invoices. This introduces potential errors. Which data concept is being addressed?
Hard57The exhibit shows a JSON schema for a dataset. Which statement correctly describes the data types represented?
Medium58An organization is implementing a data lake to store raw data from various sources. Which THREE characteristics are typically associated with a data lake compared to a data warehouse?
Easy59A company needs to store data that is highly interconnected, such as social network relationships. Which two database types are best suited for this? (Select TWO.)
Medium60A company needs to store raw, unprocessed data from IoT sensors for future machine learning experiments. The data is in various formats and schemas are not yet defined. Which storage solution is most appropriate?
Easy61A data governance team is defining roles and responsibilities for data management. Which TWO of the following are common data governance roles? (Select TWO).
Medium62A company wants to share a dataset with external partners via an API. Which API type is typically used for web services and uses XML or JSON for messaging?
Medium63Which of the following data types best describes a JSON file containing customer orders with varying fields per record?
Easy64Which of the following best describes a data mart?
Easy65Which of the following is an example of semi-structured data?
Easy66A company uses a data warehouse for reporting. They need to extract data from multiple sources, load it into a staging area, and then transform it before moving to the warehouse. This process is known as:
Medium67Which THREE characteristics describe unstructured data? (Select three.)
Hard68A healthcare organization maintains a database of patient records. The database has a table 'patients' with columns: patient_id (primary key), first_name, last_name, date_of_birth, gender, and last_visit_date. A data analyst is tasked with creating a report that lists all patients who have not visited in the last two years. The analyst writes a query: SELECT * FROM patients WHERE last_visit_date < DATEADD(year, -2, GETDATE()); However, the query returns zero rows, even though the analyst knows there are patients who have not visited for over two years. Upon inspection, the analyst discovers that the last_visit_date column contains NULL values for patients who have never visited. Which modification to the query should the analyst make to include patients with NULL last_visit_date?
Medium69Which TWO of the following are characteristics of a data lake?
Easy70Which TWO of the following are characteristics of structured data? (Choose TWO.)
Medium71Refer to the exhibit. Which data concept does this exhibit best represent?
Medium72A financial institution wants to analyze transaction networks to detect fraud rings. Which database type is best suited for this analysis?
Hard73A data analyst is troubleshooting a report that shows unusually high sales for a specific product. Upon investigation, the analyst finds that the product was returned by several customers, but the returns were recorded in a separate system and not reflected in the sales data. Which data integration concept was likely missing?
Hard74A business needs to store large volumes of raw data in its native format for future analytics. Which storage architecture is most appropriate?
Medium75A market research firm collects survey responses where customers rate satisfaction on a scale of 'Very Unsatisfied', 'Unsatisfied', 'Neutral', 'Satisfied', 'Very Satisfied'. What type of data is being collected?
Easy76A database designer wants to improve query performance on a large table that is frequently filtered by multiple columns. Which TWO types of indexes could be beneficial? (Select TWO).
Medium77A data scientist is building a machine learning model to predict customer churn. The dataset includes both numerical features (age, income) and categorical features (gender, marital status). Which data concept describes the process of converting categorical features into numerical values that can be used by the algorithm?
Hard78A DBA wants to improve query performance on a large table that is frequently filtered on two columns: department_id and hire_date. The table has millions of rows. Which index strategy would be most effective?
Hard79When the analyst runs the query, it fails. What is the most likely reason?
Medium80Drag and drop the steps for the ETL (Extract, Transform, Load) process in the correct order.
Medium81A data analyst finds that the "Age" column contains values like "N/A", "unknown", and negative numbers. Which data quality dimension is primarily affected?
Medium82Which of the following is an example of qualitative data?
Easy83A data analyst is performing a join between two tables: 'employees' and 'departments'. The 'employees' table has a foreign key 'dept_id' referencing the 'departments' table. Which two join types would include all rows from the 'employees' table, regardless of whether there is a matching department? (Select TWO)
Medium84A university database stores student information in a normalized schema. The 'students' table has a primary key 'student_id'. The 'enrollments' table has a foreign key 'student_id' referencing 'students'. Which two of the following are true about primary and foreign keys? (Select TWO)
Medium85Refer to the exhibit. An Avro schema is defined as shown. Which data design concept does this represent?
Easy86A data analyst needs to combine data from two tables: one containing customer information and another containing order details. The analyst wants to include all customers, even those who have not placed any orders. Which type of join should be used?
Medium87A data engineer is comparing data warehouses and data lakes. Which statement accurately describes a data warehouse?
Medium88A data engineer is designing a system to handle high-velocity clickstream data from a website. The system must allow low-latency writes and support key-value lookups. Which type of database is most appropriate?
Hard89Which of the following data types is characterized by a flexible schema and is commonly represented using JSON or XML?
Easy90A mid-sized e-commerce company stores customer data in a relational database. The database has a table named 'Customers' with columns: CustomerID (primary key), FirstName, LastName, Email, Phone, Address, City, State, ZipCode, and SignUpDate. The company is migrating to a new CRM system that requires a denormalized structure for performance reasons. The new system expects a single table 'CustomerDetails' with columns: CustomerID, FullName (concatenation of first and last name), ContactInfo (JSON object containing email, phone, and address), SignUpDate, and Region (derived from state). The data analyst must design an ETL process to transform the data. During a test run, the analyst notices that some records have missing Phone or Address values. Which of the following is the best approach to handle missing data in the ContactInfo JSON object?
Hard91Refer to the exhibit. The data shown is an example of which data concept?
Easy92An e-commerce company uses a star schema for its data warehouse. The fact table 'sales_fact' contains foreign keys to dimension tables: customer_dim, product_dim, time_dim, and store_dim. A business user wants to know the total sales for each product category in the last month. Which join operation is required to retrieve this data?
Medium93A sensor records temperature readings in Celsius and a separate sensor records wind speed in meters per second. A data scientist wants to combine these datasets for analysis. Which statement accurately compares these data types?
Hard94A company is designing a data pipeline to process streaming data from social media feeds. Which THREE of the following are characteristics of streaming data? (Select THREE).
Hard95Which TWO of the following are examples of data governance best practices?
Hard96A market researcher conducts a survey with questions like "What is your favorite brand?" and "How many units do you purchase per year?" Which data types correspond?
Easy97Which TWO roles are primarily responsible for defining and enforcing data governance policies within an organization?
Medium98A company stores customer data in a relational database with tables for orders, products, and customers. Which type of data best describes this?
Easy99Which TWO of the following are considered internal data sources within an organization?
Easy100A company is designing a database for an e-commerce application that requires high transaction throughput and must guarantee that each transaction is processed atomically. Which property of ACID ensures that a transaction is either fully completed or not executed at all?
Easy101A financial application requires fast query performance for aggregations on large historical datasets. The schema has many lookup tables. Which schema design is most efficient for this workload?
Medium102A retail company processes daily transactions. The current system transforms data before loading it into the data warehouse. The volume is growing rapidly, and they want to load raw data first to reduce processing time. Which approach should they adopt?
Easy103Which TWO are examples of primary data? (Select two.)
Easy104Refer to the exhibit. A data analyst is trying to understand access permissions for the company data folder. Which statement accurately describes the effective permissions?
Medium105A company is ingesting data from multiple sources into a cloud data warehouse. They decide to load the data raw and then perform transformations within the warehouse. Which approach does this describe?
Medium106During an ETL process, a data quality check fails due to duplicate customer IDs. Which data quality dimension is violated?
Hard107A company is migrating its data pipeline from on-premises to the cloud. The current ETL process transforms data before loading into a data warehouse. The new architecture will use ELT instead. Which THREE of the following are advantages of ELT over traditional ETL? (Select 3)
Hard108A data analyst needs to ensure that a customer's address is stored in a consistent format across multiple databases. Which data quality dimension is the analyst primarily concerned with?
Easy109In a customer database, each row represents a customer with columns: CustomerID, Name, Address, Phone. What does the column "Name" represent?
Medium110Refer to the exhibit. A data pipeline is failing to parse this log entry. What is the most likely cause of the error?
Easy111A data governance team is establishing policies for data quality. Which THREE of the following are common dimensions of data quality? (Select 3)
Medium112A financial services company is migrating its customer data from a legacy on-premises relational database to a cloud-based data warehouse. The legacy database uses a denormalized schema with a single table 'customer_master' that contains all customer attributes, including repeated groups for multiple accounts per customer (account1_type, account1_balance, account2_type, account2_balance, etc.). The data warehouse team wants to implement a normalized star schema with separate dimension and fact tables. During the ETL process, the team encounters an error: 'Data truncation: string data right truncation' when loading account_type values into the dim_account table. The account_type column in dim_account is defined as VARCHAR(10), but the source data contains account types like 'SavingsPlus' (11 characters) and 'CheckingPremium' (15 characters). The team must resolve this issue without losing data. Which course of action should the team take?
Hard113A data analyst needs to compare sales data from the company's internal CRM with public demographic data from a government census. Which data concept best describes this scenario?
Medium114A database administrator wants to ensure that every value in a column matches values in a primary key column of another table. Which constraint enforces this rule?
Medium115An analyst is reviewing a table that stores customer orders. The table contains columns: OrderID, CustomerName, Product1, Product1Qty, Product2, Product2Qty. This design violates which normal form?
Hard116Refer to the exhibit. A data analyst runs this query to identify high-value customers. However, the result does not include customers with exactly 5 orders. Which data concept does the HAVING clause illustrate?
Hard117A data team must implement a data retention policy to reduce storage costs while meeting legal requirements. Which TWO actions best achieve this?
Medium118A retail company is merging customer data from three separate systems: an e-commerce platform, a point-of-sale (POS) system, and a loyalty program. The e-commerce platform stores customer names in "FirstName LastName" format, the POS system stores names as "LastName, FirstName", and the loyalty program stores names in separate "first_name" and "last_name" fields. The data analyst needs to create a unified customer master table. After initial merging, there are 20% more records than expected, including duplicates with slight name variations (e.g., "John Smith" vs "John A. Smith"). To ensure accurate consolidation, which data concept should the analyst prioritize applying first?
Easy119A company is building a data pipeline to ingest sensor data from IoT devices. The data arrives continuously in small batches and must be processed in real-time for monitoring. Which type of data source best describes this scenario?
Medium120Which THREE of the following are valid methods for handling missing data?
Hard121An organization needs to store raw data from IoT sensors in its native format for future analysis. Which storage solution is best suited for this purpose?
Easy122Which of the following is an example of unstructured data?
Easy123A data governance team is implementing a program to ensure consistent definitions and quality of customer data across the organization. They assign a senior manager to be accountable for the data asset. Which role does this manager fulfill?
Medium124Refer to the exhibit. A database administrator notices that queries filtering on both CustomerID and OrderDate are slow. Which single change would most likely improve performance for such queries?
Hard125A data quality report shows that 95% of records have all required fields completed, but 20% of the completed fields contain values that are outside valid ranges. Which data quality dimension is most affected?
Medium126A data analyst is evaluating data quality issues in a customer database. Which TWO actions are best practices for ensuring data consistency?
Hard127A data governance team is establishing policies to ensure data quality. They define rules for data accuracy, completeness, and consistency. Which data governance function is primarily responsible for defining and enforcing these rules?
Hard128A data analyst is extracting data from a web page using web scraping techniques. The data will be used for market research. Which TWO of the following are common challenges associated with web scraping?
Medium129Refer to the exhibit. Which conclusion can be drawn from this data quality report?
Hard130Refer to the exhibit. Which type of data is the field "region"?
Medium131Which TWO of the following are examples of semi-structured data?
Medium132Which stage of the data lifecycle involves converting raw data into a usable format, such as cleaning or validating?
Easy133A data analyst wants to retrieve data from a REST API that returns JSON. Which step is part of the data lifecycle for this activity?
Medium134A hospital wants to analyze patient readmission rates. The data contains daily patient visits. What is the level of granularity?
Easy135A retail company analyzes customer purchase data to improve inventory management. They store daily transaction records in a relational database and monthly aggregate reports in a data warehouse. Which difference between these storage methods best explains why the warehouse is more suitable for trend analysis?
Medium136A data engineer is designing a system to store raw sensor data from thousands of IoT devices. The data will be used later for various analytics projects, but the schema is not yet defined. Which storage solution is most appropriate?
Hard137An OLTP system processes thousands of transactions per second. Which property ensures that a transaction is fully completed or fully rolled back, preventing partial updates?
Medium138A data analyst is creating a report for a marketing campaign. The campaign data includes customer names, email addresses, and purchase history. Which of the following best describes the 'customer name' data type?
Easy139Which TWO of the following are primary benefits of implementing a data governance program?
Hard140Refer to the exhibit. Which data quality dimension is compromised by the missing value for Charlie's salary?
Easy141Which THREE of the following are common characteristics of unstructured data?
Medium142An organization has multiple systems that store customer information inconsistently. To create a single authoritative view of customer data, they implement a process that identifies and merges duplicate records. This is an example of which data management discipline?
Hard143A table named Orders has columns OrderID, CustomerID, OrderDate, and TotalAmount. Which column should be the primary key to uniquely identify each order?
Medium144Which TWO of the following are examples of data transformation? (Choose TWO.)
Easy145A data analyst is working with a dataset that contains customer names and addresses. Some records have missing state codes. Which data quality issue is this?
Medium146A telecommunications company is experiencing issues with its customer satisfaction survey data. The data is collected from multiple channels: phone, email, and web forms. Each channel uses a different scale for ratings: phone uses 1-10, email uses 1-5, and web uses 1-7. Additionally, some survey responses contain missing values for demographic fields. The data analyst needs to calculate an overall satisfaction score that is comparable across all channels. The company's leadership wants a single metric that minimizes distortion from the different scales. Which approach should the analyst use to standardize the ratings?
Medium147Which TWO of the following are examples of quantitative data? (Choose TWO.)
Medium148A company is designing a data lake to store raw sensor data from IoT devices. The data arrives as JSON objects with varying schemas. Which storage approach is most appropriate?
Hard149A data analyst needs to combine rows from two tables based on a related column, but only wants rows that have matching values in both tables. Which join type should the analyst use?
Medium150A data engineer needs to store logs from web servers that have varying fields. The logs are in JSON format. Which data type describes this JSON data?
Medium151A database table has columns: OrderID (primary key), ProductID, CustomerID, CustomerName, OrderDate, ProductName. All products are purchased only by the customer who placed the order. Which normal form violation exists if CustomerName depends on CustomerID?
Hard152A data team is building a predictive model. They have data on 'Number of employees' (whole numbers) and 'Revenue' (currency). Which statement correctly compares these data types?
Medium153A data modeler is designing a dimensional model for a sales analytics system. The fact table contains sales transactions, and the dimension tables include product, customer, and time. To reduce data redundancy, the modeler normalizes the dimension tables into multiple related tables. Which schema is being implemented?
Hard154Which TWO of the following are characteristics of OLTP systems? (Select 2)
Easy155A data engineer needs to extract data from a REST API and load it into a data warehouse. The data is received in JSON format. Which data type best describes JSON?
Easy156In the data lifecycle, which phase involves converting raw data into a usable format for analysis?
Hard157A database has a table that violates 2NF because it contains a composite primary key and some attributes depend only on part of that key. Which normal form would be violated next if the table is not addressed?
Hard158A healthcare database stores patient records. Each patient has a unique patient_id, and the database includes a table 'visits' with visit_id, patient_id, visit_date, and diagnosis_code. To ensure data integrity, which constraint should be applied to the patient_id column in the 'visits' table?
Easy159Which THREE of the following are valid data quality dimensions? (Choose THREE.)
Hard160A manufacturing company has two primary data systems: an ERP system that stores production orders with fields like OrderID, ProductID, Quantity, and ProductionDate, and a CRM system that stores customer sales with fields like SaleID, CustomerID, ProductID, SaleDate, and Amount. The data analyst needs to create a unified view of product performance by joining these tables. However, the ProductID field in the ERP uses a 5-character alphanumeric code (e.g., 'P1234'), while the CRM uses a 6-character code (e.g., 'PR1234'). Additionally, some products have multiple entries due to slight variations in naming. The analyst wants to ensure accurate matching without losing data. Which action should the analyst take first to address the data inconsistency?
Medium161Which THREE of the following are characteristics of a relational database?
Medium162A company uses an OLTP system for processing customer transactions. Which characteristic is most important for this system to ensure that each transaction is processed reliably, even if multiple users access the system simultaneously?
Medium163A table Orders has OrderID (primary key), CustomerID, and CustomerEmail. During analysis, it is found that CustomerID uniquely identifies CustomerEmail. Which normal form is violated if both CustomerID and CustomerEmail are stored in this table?
Hard164A company is implementing a data lifecycle management policy. Which stage occurs immediately after data is created?
Medium165Which TWO of the following are examples of unstructured data? (Select 2)
Medium166A data architect needs to store raw data from various sources, including social media feeds and log files, for future analysis. The data may be used for machine learning and ad-hoc queries. Which storage solution is most appropriate for storing raw data in its native format?
Easy167A data analyst notices that customer addresses in the database contain invalid ZIP codes. Which data quality dimension is being violated?
Easy168Which THREE of the following are properties of ratio data? (Choose THREE.)
Hard169A dataset contains a column 'Education Level' with values: 'High School', 'Bachelor', 'Master', 'PhD'. An analyst computes the average by assigning numbers 1-4. Which data concept is being violated?
Hard170A data analyst is working with a dataset containing customer information. The dataset includes a column 'full_name' which stores first and last names together. To perform analysis on first names separately, which data concept describes the process of splitting 'full_name' into 'first_name' and 'last_name'?
Easy171A database administrator is designing a normalized database to reduce data redundancy. They have a table with columns: OrderID, ProductID, ProductName, and Quantity. The table is currently in 1NF. To move to 2NF, which issue must be resolved?
Medium172A data analyst is designing a database for a retail application. Which TWO of the following are valid reasons to use a NoSQL document database like MongoDB instead of a relational database? (Select 2)
Hard173A hospital's patient records system must process thousands of small transactions per second. Which type of database system is best suited for this workload?
Easy174Which TWO data types are considered quantitative? (Select two.)
Medium175An e-commerce company wants to provide real-time personalized product recommendations based on customer browsing behavior. Currently, they have a traditional data warehouse that processes batch updates every night. The marketing team complains that recommendations are outdated within hours because customers see yesterday's data. The data engineer needs to modify the architecture to support near-real-time analytics. The budget is limited, and the existing warehouse infrastructure must be reused as much as possible. Which architectural change would best meet the requirement?
Easy176A data analyst is working with a relational database that contains a table of customer orders. To optimize query performance for a report that filters by order date and customer ID, the analyst wants to create an index. Which type of index would be most effective for queries that filter on both columns?
Hard177A retail company has merged with another firm and now needs to create a unified customer data warehouse. The existing systems use different data classification methods: System A stores customer income as a categorical range (e.g., '$0-$50k', '$50k-$100k', '$100k+') while System B stores exact income as a decimal number. A data analyst must combine these into a single table. The goal is to perform statistical analysis that includes calculating average income, but the categorical data from System A loses precision. The analyst proposes converting System B's exact values into the same ranges as System A to ensure consistency. However, the data governance team wants to preserve as much detail as possible. Which course of action should the analyst recommend?
Hard178An organization uses a data warehouse for analytics. The data team wants to load data from source systems into the warehouse. They choose to load raw data first and then perform transformations within the warehouse. Which approach are they using?
Medium179A data analyst receives a dataset with inconsistent date formats (e.g., "01/02/2023", "2023-01-02", "Jan 2, 2023"). Which data quality dimension is most directly affected?
Medium180A data governance team is establishing policies. Which three activities are part of data governance? (Select THREE.)
Hard181Refer to the exhibit. A data architect is designing a data dictionary for a relational database. Based on the exhibit, which data concept is being illustrated?
Hard182A large online retailer stores customer orders in a PostgreSQL database. Each order has a unique order ID, and the database is normalized to 3NF. Which type of data is this?
Medium183A data analyst needs to share a weekly sales report with the marketing team. The report includes aggregated data from the data warehouse. To simplify access, the analyst creates a virtual table that encapsulates the complex query. Which database object should the analyst create?
Medium184Which database index type is most commonly used for exact-match lookups and range queries in a B-tree structure?
Easy185A data engineer is designing a data warehouse for a multinational corporation. The company has sales data from different regions with varying currencies and date formats. To ensure consistency, which data concept should be applied to standardize the data before loading into the warehouse?
Hard186A logistics company is analyzing truck delivery times. Which variable is discrete?
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