Business Intelligence Developer Assistant Interview Questions
Moreover, candidates may be asked about their problem-solving skills, ability to work effectively in a team, and communication skills. Employers may also be interested in candidates who have a strong interest in business intelligence and data analytics, as well as a willingness to learn and adapt to new technologies and trends in the field.
Overall, the main goal of the interview is to assess a candidate's technical skills, experience, and ability to work collaboratively in a fast-paced and dynamic environment.
Interviewer: Good morning, thank you for coming in today. Can you start by telling me about your previous experience in business intelligence development?
Candidate: Of course. In my previous role, I assisted in developing and maintaining a data warehouse for an e-commerce company. I also assisted in creating reports and dashboards for the marketing team.
Interviewer: Can you explain the difference between ETL and ELT?
Candidate: ETL stands for extract, transform, load while ELT stands for extract, load, transform. ETL refers to moving data from the source system to a separate data storage system where transformations are applied before loading into the destination system. Meanwhile, ELT refers to loading raw data into a destination system before transforming it in the same system.
Interviewer: How comfortable are you with writing SQL queries?
Candidate: I am extremely comfortable writing SQL queries. I have written queries in many environments including SQL Server, Oracle, and MySQL.
Interviewer: Can you give an example of a project you worked on that involved data visualization?
Candidate: Sure. I worked on a project for a healthcare company where I was responsible for creating a dashboard that displayed key performance indicators for different departments. The dashboard gave an executive-level view of the company's overall performance.
Interviewer: Can you explain how you handle missing or incomplete data in your analysis?
Candidate: When handling missing or incomplete data, I first try to understand why the data is missing. I may consult with the database administrator or data owner to determine if the issue can be resolved. If not, I use data imputation techniques to fill in the missing values with estimated values.
Interviewer: Have you worked with any cloud-based data solutions such as AWS Redshift or Google BigQuery?
Candidate: Yes, I have worked with both. In particular, I have experience with migrating data from on-premise data warehouses to cloud-based solutions like these.
Interviewer: How comfortable are you with using Excel for data analysis?
Candidate: I am comfortable using Excel for data analysis. I have used it for various data-related tasks such as organizing and manipulating data, creating graphs and tables, performing statistical analyses, and building forecasting models.
Interviewer: Can you give an example of a data-driven decision that you helped make in a previous role?
Candidate: Yes. At an e-commerce company I worked for, we used data from customer purchase histories and trends to make a decision about what products to feature on the homepage of the website. This resulted in a significant increase in sales.
Interviewer: How do you stay up to date on industry trends and best practices in business intelligence development?
Candidate: I subscribe to industry publications and attend webinars to stay up to date on trends and best practices. I also network with other business intelligence professionals and follow online communities and message boards.
Interviewer: Can you walk me through the process you use for creating a report or dashboard?
Candidate: The first step is to determine what questions the report or dashboard will answer. Once I have this, I gather the necessary data and begin to organize it in a way that is easy for the end user to understand. I then design the layout and create any visual elements such as charts or graphs. Finally, I test the report or dashboard to ensure it is accurate and functional.
Interviewer: How would you handle a situation where a stakeholder requests a report or dashboard that you know would not provide valuable insights?
Candidate: I would communicate with the stakeholder and try to understand why they are requesting the report or dashboard. I would then make a recommendation for a different visualization or layout that would provide more valuable insights based on their needs.
Interviewer: Can you give an example of how you have collaborated with other departments to create a report or dashboard?
Candidate: At my previous company, I worked with the finance department to create a report that tracked expenses and income over time. Through this collaboration, we were able to ensure that the data was accurate and easily understood by both the finance department and other stakeholders.
Interviewer: Can you explain the difference between a measure and a dimension in a dataset?
Candidate: A measure is a numerical value that represents an aspect of the data set that can be aggregated, such as revenue or number of products sold. A dimension is a category or attribute that provides context for the measure, such as date, product category, or location.
Interviewer: Can you give an example of how you have used data to identify areas for process improvement in a previous role?
Candidate: In a previous role, I analyzed data on customer complaints to identify trends and common issues. Through this analysis, I was able to identify areas where the customer experience could be improved such as better communication during the warranty period and more information provided in product manuals.
Scenario Questions
1. Scenario: You have been assigned to create a dashboard for a retail company that sells clothing items. You need to present data on the sales for different products by different regions. What visualizations do you think will be the most appropriate to use and why?
Candidate Answer: I would first create a bar chart with the different products along the X axis and the sales on the Y axis. I would then segment the chart by region. I would also create a map chart to show the sales by region, with color coding to represent different sales levels.
2. Scenario: You have been given a dataset containing information on the number of employees in different departments and their salaries. The CEO wants a report that shows the average salary per department and the total salaries for each department. Can you create such a report? Use the sample data below:
| Department | Employee Count | Total Salary |
| ---------- | --------------| ------------ |
| Marketing | 10 | $400,000 |
| Finance | 8 | $360,000 |
| HR | 6 | $240,000 |
| Sales | 12 | $480,000 |
Candidate Answer: Yes, I can create a report that shows the average salary per department and the total salaries for each department. To do this, I would use a table that shows the department name, employee count, total salary, average salary, and total salary for each department. I would then add a subtotal row that shows the total employee count, total salary, and average salary for all departments.
3. Scenario: You have been asked to analyze the customer order data for an online retailer. The CEO wants to know which products are selling the most, which products are selling less, and how much revenue is being generated. Use the sample data below:
| Product | Quantity Sold | Revenue |
| ----------- | ------------ | ------- |
| Product A | 100 | $20,000 |
| Product B | 50 | $10,000 |
| Product C | 200 | $40,000 |
| Product D | 25 | $5,000 |
Candidate Answer: To analyze the customer order data, I would create a bar chart that shows the different products along the X axis and the quantity sold and revenue generated on the Y axis. This chart will help me identify which products are selling the most and generating the most revenue. I would also create a table that shows the products, quantity sold, revenue, and percentage of total revenue.
4. Scenario: You have been given a dataset that contains information on the sales performance of a retail store over the past 6 months. The CEO wants to know how the store has performed in each month and what the trend is. Use the sample data below:
| Month | Sales |
| ----- | ----- |
| Jan | $50,000 |
| Feb | $55,000 |
| Mar | $60,000 |
| Apr | $45,000 |
| May | $50,000 |
| Jun | $65,000 |
Candidate Answer: To analyze the sales performance of the retail store, I would create a line chart that shows the sales over time. I would plot the sales on the Y axis and the months on the X axis. I would also add a trend line to the chart to show the trend over time. Additionally, I would create a table that shows the total sales for each month and the percentage change from the previous month.
5. Scenario: You have been asked to analyze the customer data for a subscription-based service. The CEO wants to know how many customers have subscribed in each month and what the trend is. Use the sample data below:
| Month | Subscribers |
| ----- | ----------- |
| Jan | 100 |
| Feb | 120 |
| Mar | 130 |
| Apr | 115 |
| May | 125 |
| Jun | 140 |
Candidate Answer: To analyze the customer data for the subscription-based service, I would create a line chart that shows the number of subscribers over time. I would plot the subscribers on the Y axis and the months on the X axis. I would also add a trend line to the chart to show the trend over time. Additionally, I would create a table that shows the total number of subscribers for each month and the percentage change from the previous month.