An analyst has a dataset with a 'Timestamp' column in ISO 8601 format with timezone offsets (e.g., '2023-05-01T12:00:00-05:00'). The analyst needs to compare events across timezones. What should the analyst do?

Keep the original timezone offsets and compare the local times.

Sort the timestamps as strings.

Remove the timezone offset from the timestamps.

What is the primary purpose of data merging?

To extract and interpret data from various formats

To standardize data into a consistent format

To remove duplicate records from a dataset

To combine datasets from different sources into one unified dataset

A data analyst merges two customer databases. In database A, the 'Email' column is lowercase; in database B, it is mixed case. The analyst needs to identify duplicate customers across the databases. Which transformation should be applied before deduplication?

Remove all email addresses that are not lowercase.

Sort the email column alphabetically.

Normalize the email addresses to lowercase in both databases.

Perform a fuzzy match on the email addresses.

A marketing analyst merges customer data from three regional offices. Each office records the 'JoinDate' field differently: '2023-01-15', '01/15/2023', and '15-Jan-2023'. Before analyzing customer tenure, what should the analyst do?

Replace all date values with the current date.

Keep the original formats and convert them only when needed for analysis.

Convert all date values to a single standard format, such as YYYY-MM-DD.

Sort the data by the string representation of the date.

An analyst combines two product databases. In one, product category is 'Electronics'; in the other, it is 'electronics'. The analyst wants a single consistent category field. Which transformation should be applied?

Remove the category column from the merged dataset.

Sort the category column alphabetically.

Perform a fuzzy match on product names to infer categories.

Apply a case-normalization function to the category column.

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Domain 2Objective 3

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Part of the Data acquisition and preparation domain, which accounts for 22% of the DA0-001 exam. CompTIA does not publish an official question count, but from its 90-minute exam (~35–60 total, ~8–13 in this domain), expect 3–4 from this objective — we provide 27 practice questions to prepare you well beyond it. (estimate)

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Questions 11–15

11expert · medium
An analyst has a dataset with a 'Timestamp' column in ISO 8601 format with timezone offsets (e.g., '2023-05-01T12:00:00-05:00'). The analyst needs to compare events across timezones. What should the analyst do?
Select an answer first
12foundation · easy
What is the primary purpose of data merging?
Select an answer first
13expert · medium
A data analyst merges two customer databases. In database A, the 'Email' column is lowercase; in database B, it is mixed case. The analyst needs to identify duplicate customers across the databases. Which transformation should be applied before deduplication?
Select an answer first
14application · medium
A marketing analyst merges customer data from three regional offices. Each office records the 'JoinDate' field differently: '2023-01-15', '01/15/2023', and '15-Jan-2023'. Before analyzing customer tenure, what should the analyst do?
Select an answer first
15application · easy
An analyst combines two product databases. In one, product category is 'Electronics'; in the other, it is 'electronics'. The analyst wants a single consistent category field. Which transformation should be applied?
Select an answer first

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