Interview Questions And Answers for Data Architects

Data architect interview questions don’t just revolve around role-specific topics, such as data warehouse solutions, ETL, and data modeling. In fact, interviewers will also challenge you with brainteasers, behavioral, and situational questions. So, how do you prepare for a successful data architect interview? In this article, you’ll learn everything you need to know about the data architect interview preparation: The skills you need to become a data architect;Real-life data architect interview questions (and answers) you should be familiar with;The data architect interview process at 3 top-tier companies. And, as an extra resource, you’ll discover how to recover from 3 common job interview mistakes. But first, let’s focus on the part you simply can’t go without – the data architect competences. Which are the top 5 skills you need to become a data architect? Here are the essential competences every data architect must demonstrate: Strong data modeling skills;Database architecture and data warehousing experience;Data governance know-how;Experience with Python or R, and SQL;Good command of data visualization tools (for example, Tableau). If you need to build up your data architect skillset, then our online Data Science program is a great place to start. You can preview the program (12 hours of video instruction) for free. What are the data architect interview questions you should expect? General Data Architect Interview Questions The more general part of the interview is not necessarily focused solely on your resume. It could also include some questions regarding the projects you’ve worked on and how you manage your time and priorities. 1. Have you ever taken part in improving a company’s existing data architecture? Please describe your involvement in the process and the overall impact the changes had on the company.How to Answer Routine tasks and maintenance are an important part of a data architect’s job. However, as a data architect, you should also be proactive and strive to improve the company’s data processes and structures. Employers want to hire data architects with a critical mindset who are willing to take part in increasing the efficiency and productivity of current environments. So, do your best to show the interviewer you don’t get preoccupied with routine tasks, and you don’t lose sight of the bigger picture. Answer Example “In my work experience, marrying external data with internal data in corporate systems can pose a variety of threats to data integrity. That’s why I launched a project where I established a step-by-step screening process for our 3-rd party purchased data. I also managed to further improve the relationship with our data supplier, who, in turn, agreed to run a few checks on their data before sending it to us. This initiative had a positive impact on the company’s data reliability and decreased database errors by 29% within 1 year.” 2. As a data architect, have you faced any challenges related to the company’s data security? How did you ensure the integrity of the data was not compromised?How to Answer Data security is a top priority for every company. That’s why hiring managers would like to learn more about your experience with data security issues. When answering this question, emphasize that data security is an important aspect of your job, although your background isn’t focused in that particular field. Answer Example “When working in a team, it’s sometimes hard to agree on what could pose a security risk. I remember a situation when some colleagues of mine wanted to change the established process for uploading franchise data to our system. I was sure theses changes could result in security risks. So, in order to validate my point, I calculated the possible financial loss to the company in case security was compromised. This prompted the team members to modify their plan to strengthen data security measures.” 3. As a data architect, you should be up to date with the latest technologies and developments in the field. How do you keep yourself informed about the new trends in data architecture?How to Answer When working in a technical role, it’s common to get absorbed in the company’s current processes and miss out on the latest industry developments. Hiring managers will value your willingness to educate yourself despite your busy schedule. So, try to list news resources you’re subscribed to, and mention some conferences or trainings, or industry events you attend when you have the chance. Answer Example “I do my best to stay informed about the latest industry trends and technology advancements. I believe this helps me learn things that can improve my work… Or inspire me to come up with an idea that will benefit the company’s status quo. I’m subscribed to newsfeeds such as InformationWeek and TechNewsWorld. I also attend 2-3 conferences a year where I network with other professionals in the field. Whenever my schedule allows it, I attend specialized trainings and seminars.” Technical Data Architect Interview Questions The technical questions in a data architect interview concentrate on your work with certain programming languages, tools, and technologies, and your ability to use them to fulfill project goals or solve unforeseen issues. 4. A lot of companies use data from both internal and internal sources. Have you faced any problems while trying to integrate a new external data source into the existing company’s infrastructures? How did you solve these problems?How to Answer External data often comes from sources using different data formats and systems. Obviously, that may cause a series of issues when importing this data into the company’s data systems. As a data architect, you have to make sure the data format is readable and ready-to-use, before storing it in the data warehouse. With this question, hiring managers want to assess your problem-solving skills when faced with external data integration challenges. So, try to provide an answer that will demonstrate how you address such issues. Answer Example “In my work experience, the cause for external data integration issues is usually a different system that creates the data in an incompatible format. Unfortunately, it isn’t possible for all companies to use the same systems. So, I solved this problem by creating and running a script prior to uploading the data in my company’s warehouse tables. The script not only changed the external data format but also ran tests to ensure the new format was compatible with our systems.” 5. Have you worked with open source technology? Tell us about some issues you have comes across when using it.How to Answer When an interviewer asks a specific question like that, the company is either considering using open source technology in the future or is already utilizing it. If you have relevant experience, give some particular examples. And be sure you also highlight your ability to modify the open source programming code. If you haven’t encountered any problems using it, mention any possible disadvantages to open source technology you’re aware of. Answer Example “I’ve worked with both Hadoop and MySQL without facing any major problems. Nevertheless, I realize that using open source databases or software utilities has its drawbacks. For example, you have to rely on advice from user forums, as there is no formal customer support to address your issue. Another thing is that developers don’t spend a lot of time on their user interface, so you may lack the resources you need to get started.” 6. State and describe the different types of SQL joins.How to Answer The basic types of SQL joins are: inner, left, and right (in SQL theory, there is one more type of join – full. However, it is used very rarely today). The easiest and most intuitive way to explain the difference between the inner, left, and right joins is by using a Venn diagram, which shows all possible logical relations between data sets. The SQL INNER JOIN lets us select all records from Table A and Table B, as long as there is a match between the columns. The SQL LEFT JOIN returns all records from the left table, plus the matched values from the right table. In case there are no matches, the left join still returns all rows from the left table and a NULL value from the right. Regarding the functionality of the SQL RIGHT JOINS – it is identical to LEFT JOINS, but with the opposite direction of the operation. Author’s note: If you’re eager to learn more about SQL JOINS, check out our dedicated tutorials on the topic: Introduction to SQL Joins, How to Create an Inner Join in SQL, Working with the LEFT JOIN in SQL, and Introducing the RIGHT JOIN in SQL. 7. What is a primary key and a foreign key?How to Answer A primary key is a column (or a set of columns) whose value exists and is unique for every record in a table. It’s important to know that each table can have one and only one primary key. Therefore, you can think of a primary key as the field (or group of fields) that identifies the content of a table in a unique way. For this reason, the primary keys are also called the unique identifiers of a table. Another crucial feature of primary keys is they cannot contain null values. This means, in an example with a single-column primary key, there must always be a value inserted in the rows under this column. You cannot leave it blank. One last remark about primary keys – not all tables you work with will have a primary key, although almost all tables in any database will have a single-column or a multi-column primary key. A foreign key, instead, is a column (or a set of columns) that references a column (most often the primary key) of another table. Foreign keys can be called identifiers, too, but they identify the relationships between tables, not the tables themselves. In the relational schemas form of representation, relations between tables are expressed in the following way – the column name that designates the logical match is a foreign key in one table, and it is connected with a corresponding column from another table. Often, the relationship goes from a foreign key to a primary key, but in more advanced circumstances, this will not be the case. To catch the relations on which a database is built, we should always look for the foreign keys, as they show us where the relations are. Author’s note: for a more in-depth explanation, check out our tutorials on SQL Primary Key and SQL Foreign Key. 8. How many types of data structures does R have?How to Answer This question is important because virtually everything you do in R involves data in some shape or form. The most commonly used data structures in R are these: Vectors (atomic and lists);Matrixes;Data frames;Factors.9. What modeling tools have you used in your work so far? Which do you consider efficient or powerful?How to Answer Even if data modeling isn’t one of your main responsibilities, your role as a data architect requires you to have an in-depth understanding of data modeling. If you lack the experience, demonstrate that you are well-informed on the topic and mention the data modeling tools you find most useful. The interviewer will value that you’re at least familiar with the subject. Answer Example “I’ve used mainly both Oracle SQL Developer Data Modeler, and PowerDesigner. I can say that the Oracle Data Modeler has been more than sufficient for my needs with its dimensional modeling, and integrated source code control that supports collaborative development. However, PowerDesigner also boasts some wonderful technology-centric metadata management capabilities for data architects, and business-centric techniques for non-technical coworkers. Overall, I think both tools are worth the try, depending on the company’s needs.” By the way, if you’re finding this answer useful, consider sharing this article, so others can benefit from it, too. Helping fellow aspiring data architects reach their goals is one of the things that make the data science community special. 10. What’s your experience with batch and real-time data processing?How to Answer Each of these data processing methods can be applied depending on the business case. If you have experience with only one of them, provide examples of situations where the other processing method would be a better fit. This will indicate you have a basic understanding of both batch and real-time data processing. Answer Example ‘I’m familiar with both types of data processing. However, I’ve had more exposure to batch processing. That’s because one of my responsibilities was to write programs that captured, processed, and produced output for the company’s billing department. As I mentioned, I’ve had less experience with real-time data processing. However, I know our company uses it to take immediate action on the data collected from our stores’ POS systems.” 11. In your role as a data architect, what metrics have you created or used to measure the quality of new and existing data?How to Answer Having established processes to ensure the quality of data is key to a company’s data infrastructure. With this question, the hiring manager wants to assess your relevant experience. Make sure you highlight the particular dimensions you’ve monitored to validate the data quality. Answer Example “I’ve always been involved in ensuring data quality in my job as a data architect. My team and I monitored some specific dimensions to validate the quality of data. These included completeness, uniqueness, timeliness, validity, accuracy, and consistency. Monitoring these dimensions helped us detect inconsistencies that could negatively affect the accuracy of data analysis.” Behavioral Questions Data architects often work with coworkers from various departments, backgrounds, and responsibilities. This is why you should be prepared to answer some behavioral questions focused on your work style and ability to handle conflict in cross-functional teams. 12. What challenges have you faced working with colleagues with no technical background? How did you address and overcome these challenges?How to Answer Data architects often work with other departments within a company. That involves collaborating with people who lack technical background and understanding of the data processes. The interviewer would like to assess your communication style and your ability to reach common ground with your coworkers, in spite of your differences. Describe a specific situation to illustrate the issues you encountered and how you solved them. Answer Example “I believe a good data architect should understand the needs of the different departments across the company. That said, I’ve had to work with people who don’t fully understand my role and responsibilities on numerous occasions. Some of my coworkers would pose requests that I had to reject due to our data architecture limitations. And that has lead to certain tensions. I’d say overcoming such challenges takes time. Gradually, we learned more about each other’s work which helped us brainstorm possible solutions. All in all, making the extra step to educate myself and the others made has made all the difference.” 13. How would you describe your work style?How to Answer This question is not so much about your personality, but more about how you approach your work to get things done. Talk about the way you handle tasks and projects, and how you communicate with coworkers and clients. Your work style might be: collaborative, well-structured, speedy, flexible, or independent. No matter what word you choose to describe it, keep the job description in mind and how your work style fits the profile. Answer Example “I’d describe my work style as collaborative. I like to work on full-team participation projects and co-create with my teammates. If I’m not sure of the direction I should take on a project, I always consult with my team. This way we can work toward consensus and align our ideas.” 14. How would you resolve a conflict within your team?How to Answer The hiring manager wants to hear about your ability to professionally solve team issues when they occur. Think of an example where you had to use your communication skills to handle a conflict with your coworkers. Or when you managed to help 2 of your teammates find common ground as a mediator. Answer Example “I like to think I have excellent conflict management skills. As a data architect in a large company, I’ve worked in a high-stress environment. And that has sometimes caused tension to build up among team members. When this escalates to a conflict, I try to deal with it openly. Usually, I’d organize a group meeting where everyone can voice their concerns. This is how we can sort out the issue and move on with our work on the project.” 15. What is the most critical factor for you when taking a job?How to Answer There are a lot of factors that may influence your decision to take on a new job. These include: – career growth opportunity; – compensation; – work/life balance; – travel required for the role; – medical and dental benefits; – perks such as a gym membership, onsite kids center, spending account; – paid vacation time; – the company’s location; – the company’s reputation and culture. Share with the interviewer which factors are most important to you when you consider starting a new job. If you aren’t sure about all the details regarding this position, this is a good time to get informed. Answer Example “The most important factors for me, as a data architect, are the company’s industry and the workplace culture. The first one predefines the projects I’ll be involved in. The second one indicates if the work environment will be positive and teamwork-oriented. To me, those are equally important to compensation and benefits.” 16. Are you also interviewing with any of our close competitors?How to Answer If the interviewer wants to know if you’re also applying for a job at a competitor’s company, you can give a direct answer. However, you should refrain from giving away the name of the company or sharing too many details. Let the interviewer know you aren’t putting all of your eggs in one basket. At the same time, try to leave the impression that you are critical when it comes to the companies you apply at. Answer Example “I wouldn’t disclose the names of the competitors I’m currently interviewing with. However, I can tell you that I’m in the mid-interview stages with 3 other companies. That said, your company is my first choice and I’m happy that we’ve reached the final stage in the process. 17. How would you assess your performance in the data architect interview questions so far?How to Answer This is a question you should answer openly. Generally, you would know if you performed well, or if your interview was a disaster. In fact, if you address the issues of your performance, you might get a chance to answer some additional questions that could give you extra points.” Answer Example If you think that your performance in the interview is going great: “I’m positive that the interview has been quite successful and I’m satisfied with my performance. Is there anything you’d like me to clarify from our talk?” If you think that your performance in the interview is not satisfactory: “I don’t think I managed to portray myself in the best light possible in this interview. However, I’m always trying to do my best. So, if there’s anything I could further clarify for you, I’d be more than happy to do so.” Brainteasers – Data Architect Interview Questions Brainteasers help the interviewer assess your logical thinking combined with your ability to come up with a creative problem solution on the spot. 18. What is the sum of the numbers from 1 to 100? There’s a little bit of history coming with this question. The math teacher of young Karl Gauss, the famous mathematician, asked the entire class to sum the numbers from 1 to 100. He expected that the task would require at least half an hour to his students, but was shocked when Gauss gave him the exact number within mere seconds. Anyway, here is how this question is solved. There are precisely 50 pairs of numbers from 1 to 100, whose sum is 101. 1 + 100 = 101, 2 + 99 = 101, 3 + 98 =101, etc. 50 * 101 = 5050 This trick will work for any series of numbers provided that they are evenly spaced. You need to find the sum of the first and the last number and then multiply by the number of pairs. 19. You are given two containers – one is 5 and the other one is 7 gallons. How do you use them to measure 4 gallons of water? Fill the entire 7 gallon container with water. Then use the water in the 7 gallon container in order to fill the entire 5 gallon container. This would leave 2 gallons of water in the 7 gallon container. Dump the water in the 5 gallon container and then pour in it the 2 gallons of water that are in the 7 gallon container. Fill the entire 7 gallon container with water and then start pouring the water in the 5 gallon container. Given that it is already filled with 2 gallons of water, you will be able to pour only 3 gallons, which means that 4 gallons would remain within the 7 gallon container. This is how you are able to measure 4 gallons of water. Guesstimate – Data Architect Interview Questions Guestimates are not necessarily a part of each data architect interview. However, if the interviewer decides to throw you a curve ball, you should be prepared. Here’s an example: 20. How many flat screen TVs have been sold in Australia in the past 12 months? The population of Australia is approximately 24 million. Let’s assume that the average household comprises of 2 people (there are a lot of families with 3 or 4 people, but this is balanced by those people who are living alone). So the number of homes is 12 million (provided that all people have a home). Then we need to find out how many of the TVs in these 12 million homes will need to be replaced with new ones. Let’s assume that people need to replace their old TV with a new TV every six years and that every home has 1.5 TVs. Nowadays, it is reasonable to expect that all new TVs that are purchased have a flat screen. Therefore, the number of flat screen TVs that are purchased in Australia in one year is equal to: 1/6 of the homes buy a new TV this year * 12 million homes * 1,5 TVs per home = 3 million flat screen TVs. What’s the data architect interview process like? What to expect from a data architect interview process? Technical phone screens, onsite interviews with team members, or a lunch meeting with your potential manager? Well, all of the above. However, interview processes vary depending on the company’s unique policy and recruitment approach. So, here’s what you need to know about the data architect job interview at three top-notch companies – Netflix, Microsoft, and Apple. We’re positive these brief overviews will give you a good impression of what happens behind closed doors. Netflix Data Architect Interview Questions Usually, the process starts with 2 phone interviews that revolve around more general background and professional experience questions – one with a recruiter, and then another one with the hiring manager. The phone screens are followed by two onsite interviews. The first one is with 3-4 people from the data architect team. So, you can expect plenty of database systems, software design patterns, virtual warehousing, and some programming questions. The interviewers will also ask you to analyze a hypothetical problem and enumerate various possible data architecture solutions. In the second interview, you will meet higher-level executives which means some behavioral and situational questions will come your way. Microsoft Data Architect Interview Questions The data architect interview process usually starts with a phone interview that covers your areas of expertise, previous job experience, and future plans. The interviewer will most probably ask you about the Microsoft technologies you’ve used to build solutions and the challenges you’ve encountered while implementing them. The phone screen is followed by 4-5 onsite interviews, often with 2 different teams. Around half of them are focused on data architecture. Those include scenario-based data architecture questions where you should list the pros and cons of all possibilities you can think of and what decision you’d make based on the company’s needs. Another thing the interviewers will test is your coding skills. As in other corporations, you only reach the hiring manager if you have passed the data architect interviews with the teams. Once the Hiring Manager has made a decision, you should receive timely feedback. But if you don’t have an answer from HR within a week, there is no harm in sending a friendly reminder. Apple Data Architect Interview Questions The Apple data architect interview is quite standard – you’ll have a phone screen with a recruiter first, followed by a few technical data architect phone interviews with team members. If you pass them successfully, the recruiter will give you an overview of the process prior to the onsite data architect interviews. You’ll have 6 to 8 interviews with members of the data architect team and some senior employees the team works with. There are both 1-on-1 and 2-on-1 interviews, plus a lunch interview with your potential manager. Similar to other companies, interviewers’ questions are centered around different areas and the interviewers refrain from sharing their feedback during the process. However, prepare for some data mart, dimension tables, as well as star and snowflake schema questions. Once that stage is over, your interviewers will compare notes. Then, only if they are sure that you’re a good prospect for the data architect job, you’ll have interviews with the director and the VP of the company (who, of course, has the final say). Usually, you’ll hear from a recruiter in a few days. But if it takes longer, you can send a kind request for updates. And remember, Apple employees are huge Apple fans. So, even if being a Mac user isn’t a prerequisite, you should demonstrate some knowledge (and definitely some enthusiasm) about its products. Three Common job interview mistakes (and how to recover from them) Once you start going to data architecture interviews, you’re bound to stumble upon a challenging question or a quirky comment (and interviewers particularly love throwing these to test the candidate’s reaction). So how do you recover from an interview foul? Here are 3 common mistakes and techniques that will help you take charge of the situation and stay in the interview game. Complaining about your previous job Okay. Nobody wants to hear you complain about your bad experiences at your previous job. Especially the hiring manager at your potential new job interview. Doing so signals your future employer that you aren’t loyal to your company. But what if an unpleasant comment slips your tongue? Well, in this case, there’s no way around it but to admit to your mistake and apologize. For example, if you stated that your previous employer didn’t appreciate you, apologize and then rephrase what you said: “What I was trying to say is that I felt I could be much more productive and contribute more to the company’s accomplishments.” This way the interviewer will know you’ve realized your mistake and are trying to correct it. Lack of plans for the future Sharing with the interviewer that you have no idea where you’ll be 5 years from now is likely to be interpreted as: “I don’t care about my future or your company.” If you make that mistake, offer an explanation: “Before setting goals, I’d like to acquire the skills necessary to help your company reach its long-term goals and stay ahead of the competition”. That will show that you are ambitious, but you won’t leave the company in the next few years. Not knowing the answer Hiring managers are aware that you can’t possibly have an immediate answer to all questions. Nevertheless, openly stating you don’t know the answer during an interview leaves you in a vulnerable position. So how do you recover from that? Say “This is an intriguing question and I need more time to think. May I take a few hours to consider it and send you the answer?” If the interviewer accepts your proposal, research the question thoroughly and make sure you deliver the answer within the agreed time frame. In Conclusion As a final takeaway, having a positive attitude is extremely important, especially if you’ve remained unemployed for a longer period. Companies want positive and competent people on their team, so find a way to keep your head up and exude confidence. If you want to check out more data architect interview questions, follow the link to our all-comprising article Data Science Interview Questions. However, if you feel that you lack some of the essential skills required for the job, check out the complete Data Science Program. In case you aren’t sure you want to turn your interest in data science into a full-fledged career, we also offer a free preview version of the Data Science Program. You’ll receive 12 hours of beginner to advanced content for free. It’s a great way to see if the program is right for you. Data architect interview questions don’t just revolve around role-specific topics, such as data warehouse solutions, ETL, and data modeling. In fact, interviewers will also challenge you with brainteasers, behavioral, and situational questions. So, how do you prepare for a successful data architect interview? In this article, you’ll learn everything you need to know about the data architect interview preparation: The skills you need to become a data architect ;Real-life data architect interview questions (and answers) you should be familiar with;The data architect interview process at 3 top-tier companies. become a data architect And, as an extra resource, you’ll discover how to recover from 3 common job interview mistakes. But first, let’s focus on the part you simply can’t go without – the data architect competences. Which are the top 5 skills you need to become a data architect? Here are the essential competences every data architect must demonstrate: Strong data modeling skills;Database architecture and data warehousing experience;Data governance know-how;Experience with Python or R, and SQL;Good command of data visualization tools (for example, Tableau). If you need to build up your data architect skillset, then our online Data Science program is a great place to start. You can preview the program (12 hours of video instruction) for free. If you need to build up your data architect skillset, then our online Data Science program is a great place to start. You can preview the program (12 hours of video instruction) for free. preview the program (12 hours of video instruction) for free. What are the data architect interview questions you should expect? General Data Architect Interview Questions The more general part of the interview is not necessarily focused solely on your resume. It could also include some questions regarding the projects you’ve worked on and how you manage your time and priorities. 1. Have you ever taken part in improving a company’s existing data architecture? Please describe your involvement in the process and the overall impact the changes had on the company.How to Answer Routine tasks and maintenance are an important part of a data architect’s job. However, as a data architect, you should also be proactive and strive to improve the company’s data processes and structures. Employers want to hire data architects with a critical mindset who are willing to take part in increasing the efficiency and productivity of current environments. So, do your best to show the interviewer you don’t get preoccupied with routine tasks, and you don’t lose sight of the bigger picture. Answer Example “In my work experience, marrying external data with internal data in corporate systems can pose a variety of threats to data integrity. That’s why I launched a project where I established a step-by-step screening process for our 3-rd party purchased data. I also managed to further improve the relationship with our data supplier, who, in turn, agreed to run a few checks on their data before sending it to us. This initiative had a positive impact on the company’s data reliability and decreased database errors by 29% within 1 year.” 2. As a data architect, have you faced any challenges related to the company’s data security? How did you ensure the integrity of the data was not compromised?How to Answer Data security is a top priority for every company. That’s why hiring managers would like to learn more about your experience with data security issues. When answering this question, emphasize that data security is an important aspect of your job, although your background isn’t focused in that particular field. Answer Example “When working in a team, it’s sometimes hard to agree on what could pose a security risk. I remember a situation when some colleagues of mine wanted to change the established process for uploading franchise data to our system. I was sure theses changes could result in security risks. So, in order to validate my point, I calculated the possible financial loss to the company in case security was compromised. This prompted the team members to modify their plan to strengthen data security measures.” 3. As a data architect, you should be up to date with the latest technologies and developments in the field. How do you keep yourself informed about the new trends in data architecture?How to Answer When working in a technical role, it’s common to get absorbed in the company’s current processes and miss out on the latest industry developments. Hiring managers will value your willingness to educate yourself despite your busy schedule. So, try to list news resources you’re subscribed to, and mention some conferences or trainings, or industry events you attend when you have the chance. Answer Example “I do my best to stay informed about the latest industry trends and technology advancements. I believe this helps me learn things that can improve my work… Or inspire me to come up with an idea that will benefit the company’s status quo. I’m subscribed to newsfeeds such as InformationWeek and TechNewsWorld. I also attend 2-3 conferences a year where I network with other professionals in the field. Whenever my schedule allows it, I attend specialized trainings and seminars.” Technical Data Architect Interview Questions The technical questions in a data architect interview concentrate on your work with certain programming languages, tools, and technologies, and your ability to use them to fulfill project goals or solve unforeseen issues. 4. A lot of companies use data from both internal and internal sources. Have you faced any problems while trying to integrate a new external data source into the existing company’s infrastructures? How did you solve these problems?How to Answer External data often comes from sources using different data formats and systems. Obviously, that may cause a series of issues when importing this data into the company’s data systems. As a data architect, you have to make sure the data format is readable and ready-to-use, before storing it in the data warehouse. With this question, hiring managers want to assess your problem-solving skills when faced with external data integration challenges. So, try to provide an answer that will demonstrate how you address such issues. Answer Example “In my work experience, the cause for external data integration issues is usually a different system that creates the data in an incompatible format. Unfortunately, it isn’t possible for all companies to use the same systems. So, I solved this problem by creating and running a script prior to uploading the data in my company’s warehouse tables. The script not only changed the external data format but also ran tests to ensure the new format was compatible with our systems.” 5. Have you worked with open source technology? Tell us about some issues you have comes across when using it.How to Answer When an interviewer asks a specific question like that, the company is either considering using open source technology in the future or is already utilizing it. If you have relevant experience, give some particular examples. And be sure you also highlight your ability to modify the open source programming code. If you haven’t encountered any problems using it, mention any possible disadvantages to open source technology you’re aware of. Answer Example “I’ve worked with both Hadoop and MySQL without facing any major problems. Nevertheless, I realize that using open source databases or software utilities has its drawbacks. For example, you have to rely on advice from user forums, as there is no formal customer support to address your issue. Another thing is that developers don’t spend a lot of time on their user interface, so you may lack the resources you need to get started.” 6. State and describe the different types of SQL joins.How to Answer The basic types of SQL joins are: inner, left, and right (in SQL theory, there is one more type of join – full. However, it is used very rarely today). The easiest and most intuitive way to explain the difference between the inner, left, and right joins is by using a Venn diagram, which shows all possible logical relations between data sets. The SQL INNER JOIN lets us select all records from Table A and Table B, as long as there is a match between the columns. The SQL LEFT JOIN returns all records from the left table, plus the matched values from the right table. In case there are no matches, the left join still returns all rows from the left table and a NULL value from the right. Regarding the functionality of the SQL RIGHT JOINS – it is identical to LEFT JOINS, but with the opposite direction of the operation. Author’s note: If you’re eager to learn more about SQL JOINS, check out our dedicated tutorials on the topic: Introduction to SQL Joins , How to Create an Inner Join in SQL , Working with the LEFT JOIN in SQL , and Introducing the RIGHT JOIN in SQL . Author’s note: If you’re eager to learn more about SQL JOINS, check out our dedicated tutorials on the topic: Introduction to SQL Joins Introduction to SQL Joins , How to Create an Inner Join in SQL How to Create an Inner Join in SQL , Working with the LEFT JOIN in SQL Working with the LEFT JOIN in SQL , and Introducing the RIGHT JOIN in SQL Introducing the RIGHT JOIN in SQL . 7. What is a primary key and a foreign key?How to Answer A primary key is a column (or a set of columns) whose value exists and is unique for every record in a table. It’s important to know that each table can have one and only one primary key. Therefore, you can think of a primary key as the field (or group of fields) that identifies the content of a table in a unique way. For this reason, the primary keys are also called the unique identifiers of a table. Another crucial feature of primary keys is they cannot contain null values. This means, in an example with a single-column primary key, there must always be a value inserted in the rows under this column. You cannot leave it blank. One last remark about primary keys – not all tables you work with will have a primary key, although almost all tables in any database will have a single-column or a multi-column primary key. A foreign key, instead, is a column (or a set of columns) that references a column (most often the primary key) of another table. Foreign keys can be called identifiers, too, but they identify the relationships between tables, not the tables themselves. In the relational schemas form of representation, relations between tables are expressed in the following way – the column name that designates the logical match is a foreign key in one table, and it is connected with a corresponding column from another table. Often, the relationship goes from a foreign key to a primary key, but in more advanced circumstances, this will not be the case. To catch the relations on which a database is built, we should always look for the foreign keys, as they show us where the relations are. Author’s note: for a more in-depth explanation, check out our tutorials on SQL Primary Key and SQL Foreign Key . Author’s note: for a more in-depth explanation, check out our tutorials on SQL Primary Key SQL Primary Key and SQL Foreign Key SQL Foreign Key . 8. How many types of data structures does R have?How to Answer This question is important because virtually everything you do in R involves data in some shape or form. The most commonly used data structures in R are these: Vectors (atomic and lists);Matrixes;Data frames;Factors.9. What modeling tools have you used in your work so far? Which do you consider efficient or powerful?How to Answer Even if data modeling isn’t one of your main responsibilities, your role as a data architect requires you to have an in-depth understanding of data modeling. If you lack the experience, demonstrate that you are well-informed on the topic and mention the data modeling tools you find most useful. The interviewer will value that you’re at least familiar with the subject. Answer Example “I’ve used mainly both Oracle SQL Developer Data Modeler, and PowerDesigner. I can say that the Oracle Data Modeler has been more than sufficient for my needs with its dimensional modeling, and integrated source code control that supports collaborative development. However, PowerDesigner also boasts some wonderful technology-centric metadata management capabilities for data architects, and business-centric techniques for non-technical coworkers. Overall, I think both tools are worth the try, depending on the company’s needs.” By the way, if you’re finding this answer useful, consider sharing this article, so others can benefit from it, too. Helping fellow aspiring data architects reach their goals is one of the things that make the data science community special. By the way, if you’re finding this answer useful, consider sharing this article, so others can benefit from it, too. Helping fellow aspiring data architects reach their goals is one of the things that make the data science community special. 10. What’s your experience with batch and real-time data processing?How to Answer Each of these data processing methods can be applied depending on the business case. If you have experience with only one of them, provide examples of situations where the other processing method would be a better fit. This will indicate you have a basic understanding of both batch and real-time data processing. Answer Example ‘I’m familiar with both types of data processing. However, I’ve had more exposure to batch processing. That’s because one of my responsibilities was to write programs that captured, processed, and produced output for the company’s billing department. As I mentioned, I’ve had less experience with real-time data processing. However, I know our company uses it to take immediate action on the data collected from our stores’ POS systems.” 11. In your role as a data architect, what metrics have you created or used to measure the quality of new and existing data?How to Answer Having established processes to ensure the quality of data is key to a company’s data infrastructure. With this question, the hiring manager wants to assess your relevant experience. Make sure you highlight the particular dimensions you’ve monitored to validate the data quality. Answer Example “I’ve always been involved in ensuring data quality in my job as a data architect. My team and I monitored some specific dimensions to validate the quality of data. These included completeness, uniqueness, timeliness, validity, accuracy, and consistency. Monitoring these dimensions helped us detect inconsistencies that could negatively affect the accuracy of data analysis.” Behavioral Questions Data architects often work with coworkers from various departments, backgrounds, and responsibilities. This is why you should be prepared to answer some behavioral questions focused on your work style and ability to handle conflict in cross-functional teams. 12. What challenges have you faced working with colleagues with no technical background? How did you address and overcome these challenges?How to Answer Data architects often work with other departments within a company. That involves collaborating with people who lack technical background and understanding of the data processes. The interviewer would like to assess your communication style and your ability to reach common ground with your coworkers, in spite of your differences. Describe a specific situation to illustrate the issues you encountered and how you solved them. Answer Example “I believe a good data architect should understand the needs of the different departments across the company. That said, I’ve had to work with people who don’t fully understand my role and responsibilities on numerous occasions. Some of my coworkers would pose requests that I had to reject due to our data architecture limitations. And that has lead to certain tensions. I’d say overcoming such challenges takes time. Gradually, we learned more about each other’s work which helped us brainstorm possible solutions. All in all, making the extra step to educate myself and the others made has made all the difference.” 13. How would you describe your work style?How to Answer This question is not so much about your personality, but more about how you approach your work to get things done. Talk about the way you handle tasks and projects, and how you communicate with coworkers and clients. Your work style might be: collaborative, well-structured, speedy, flexible, or independent. No matter what word you choose to describe it, keep the job description in mind and how your work style fits the profile. Answer Example “I’d describe my work style as collaborative. I like to work on full-team participation projects and co-create with my teammates. If I’m not sure of the direction I should take on a project, I always consult with my team. This way we can work toward consensus and align our ideas.” 14. How would you resolve a conflict within your team?How to Answer The hiring manager wants to hear about your ability to professionally solve team issues when they occur. Think of an example where you had to use your communication skills to handle a conflict with your coworkers. Or when you managed to help 2 of your teammates find common ground as a mediator. Answer Example “I like to think I have excellent conflict management skills. As a data architect in a large company, I’ve worked in a high-stress environment. And that has sometimes caused tension to build up among team members. When this escalates to a conflict, I try to deal with it openly. Usually, I’d organize a group meeting where everyone can voice their concerns. This is how we can sort out the issue and move on with our work on the project.” 15. What is the most critical factor for you when taking a job?How to Answer There are a lot of factors that may influence your decision to take on a new job. These include: – career growth opportunity; – compensation; – work/life balance; – travel required for the role; – medical and dental benefits; – perks such as a gym membership, onsite kids center, spending account; – paid vacation time; – the company’s location; – the company’s reputation and culture. Share with the interviewer which factors are most important to you when you consider starting a new job. If you aren’t sure about all the details regarding this position, this is a good time to get informed. Answer Example “The most important factors for me, as a data architect, are the company’s industry and the workplace culture. The first one predefines the projects I’ll be involved in. The second one indicates if the work environment will be positive and teamwork-oriented. To me, those are equally important to compensation and benefits.” 16. Are you also interviewing with any of our close competitors?How to Answer If the interviewer wants to know if you’re also applying for a job at a competitor’s company, you can give a direct answer. However, you should refrain from giving away the name of the company or sharing too many details. Let the interviewer know you aren’t putting all of your eggs in one basket. At the same time, try to leave the impression that you are critical when it comes to the companies you apply at. Answer Example “I wouldn’t disclose the names of the competitors I’m currently interviewing with. However, I can tell you that I’m in the mid-interview stages with 3 other companies. That said, your company is my first choice and I’m happy that we’ve reached the final stage in the process. 17. How would you assess your performance in the data architect interview questions so far?How to Answer This is a question you should answer openly. Generally, you would know if you performed well, or if your interview was a disaster. In fact, if you address the issues of your performance, you might get a chance to answer some additional questions that could give you extra points.” Answer Example If you think that your performance in the interview is going great: “I’m positive that the interview has been quite successful and I’m satisfied with my performance. Is there anything you’d like me to clarify from our talk?” If you think that your performance in the interview is not satisfactory: “I don’t think I managed to portray myself in the best light possible in this interview. However, I’m always trying to do my best. So, if there’s anything I could further clarify for you, I’d be more than happy to do so.” Brainteasers – Data Architect Interview Questions Brainteasers help the interviewer assess your logical thinking combined with your ability to come up with a creative problem solution on the spot. 18. What is the sum of the numbers from 1 to 100? There’s a little bit of history coming with this question. The math teacher of young Karl Gauss, the famous mathematician, asked the entire class to sum the numbers from 1 to 100. He expected that the task would require at least half an hour to his students, but was shocked when Gauss gave him the exact number within mere seconds. Anyway, here is how this question is solved. There are precisely 50 pairs of numbers from 1 to 100, whose sum is 101. 1 + 100 = 101, 2 + 99 = 101, 3 + 98 =101, etc. 50 * 101 = 5050 This trick will work for any series of numbers provided that they are evenly spaced. You need to find the sum of the first and the last number and then multiply by the number of pairs. 19. You are given two containers – one is 5 and the other one is 7 gallons. How do you use them to measure 4 gallons of water? Fill the entire 7 gallon container with water. Then use the water in the 7 gallon container in order to fill the entire 5 gallon container. This would leave 2 gallons of water in the 7 gallon container. Dump the water in the 5 gallon container and then pour in it the 2 gallons of water that are in the 7 gallon container. Fill the entire 7 gallon container with water and then start pouring the water in the 5 gallon container. Given that it is already filled with 2 gallons of water, you will be able to pour only 3 gallons, which means that 4 gallons would remain within the 7 gallon container. This is how you are able to measure 4 gallons of water. Guesstimate – Data Architect Interview Questions Guestimates are not necessarily a part of each data architect interview. However, if the interviewer decides to throw you a curve ball, you should be prepared. Here’s an example: 20. How many flat screen TVs have been sold in Australia in the past 12 months? The population of Australia is approximately 24 million. Let’s assume that the average household comprises of 2 people (there are a lot of families with 3 or 4 people, but this is balanced by those people who are living alone). So the number of homes is 12 million (provided that all people have a home). Then we need to find out how many of the TVs in these 12 million homes will need to be replaced with new ones. Let’s assume that people need to replace their old TV with a new TV every six years and that every home has 1.5 TVs. Nowadays, it is reasonable to expect that all new TVs that are purchased have a flat screen. Therefore, the number of flat screen TVs that are purchased in Australia in one year is equal to: 1/6 of the homes buy a new TV this year * 12 million homes * 1,5 TVs per home = 3 million flat screen TVs. What’s the data architect interview process like? What to expect from a data architect interview process? Technical phone screens, onsite interviews with team members, or a lunch meeting with your potential manager? Well, all of the above. However, interview processes vary depending on the company’s unique policy and recruitment approach. So, here’s what you need to know about the data architect job interview at three top-notch companies – Netflix, Microsoft, and Apple. We’re positive these brief overviews will give you a good impression of what happens behind closed doors. Netflix Data Architect Interview Questions Usually, the process starts with 2 phone interviews that revolve around more general background and professional experience questions – one with a recruiter, and then another one with the hiring manager. The phone screens are followed by two onsite interviews. The first one is with 3-4 people from the data architect team. So, you can expect plenty of database systems, software design patterns, virtual warehousing, and some programming questions. The interviewers will also ask you to analyze a hypothetical problem and enumerate various possible data architecture solutions. In the second interview, you will meet higher-level executives which means some behavioral and situational questions will come your way. Microsoft Data Architect Interview Questions The data architect interview process usually starts with a phone interview that covers your areas of expertise, previous job experience, and future plans. The interviewer will most probably ask you about the Microsoft technologies you’ve used to build solutions and the challenges you’ve encountered while implementing them. The phone screen is followed by 4-5 onsite interviews, often with 2 different teams. Around half of them are focused on data architecture. Those include scenario-based data architecture questions where you should list the pros and cons of all possibilities you can think of and what decision you’d make based on the company’s needs. Another thing the interviewers will test is your coding skills. As in other corporations, you only reach the hiring manager if you have passed the data architect interviews with the teams. Once the Hiring Manager has made a decision, you should receive timely feedback. But if you don’t have an answer from HR within a week, there is no harm in sending a friendly reminder. Apple Data Architect Interview Questions The Apple data architect interview is quite standard – you’ll have a phone screen with a recruiter first, followed by a few technical data architect phone interviews with team members. If you pass them successfully, the recruiter will give you an overview of the process prior to the onsite data architect interviews. You’ll have 6 to 8 interviews with members of the data architect team and some senior employees the team works with. There are both 1-on-1 and 2-on-1 interviews, plus a lunch interview with your potential manager. Similar to other companies, interviewers’ questions are centered around different areas and the interviewers refrain from sharing their feedback during the process. However, prepare for some data mart, dimension tables, as well as star and snowflake schema questions. Once that stage is over, your interviewers will compare notes. Then, only if they are sure that you’re a good prospect for the data architect job, you’ll have interviews with the director and the VP of the company (who, of course, has the final say). Usually, you’ll hear from a recruiter in a few days. But if it takes longer, you can send a kind request for updates. And remember, Apple employees are huge Apple fans. So, even if being a Mac user isn’t a prerequisite, you should demonstrate some knowledge (and definitely some enthusiasm) about its products. Three Common job interview mistakes (and how to recover from them) Once you start going to data architecture interviews, you’re bound to stumble upon a challenging question or a quirky comment (and interviewers particularly love throwing these to test the candidate’s reaction). So how do you recover from an interview foul? Here are 3 common mistakes and techniques that will help you take charge of the situation and stay in the interview game. Complaining about your previous job Okay. Nobody wants to hear you complain about your bad experiences at your previous job. Especially the hiring manager at your potential new job interview. Doing so signals your future employer that you aren’t loyal to your company. But what if an unpleasant comment slips your tongue? Well, in this case, there’s no way around it but to admit to your mistake and apologize. For example, if you stated that your previous employer didn’t appreciate you, apologize and then rephrase what you said: “What I was trying to say is that I felt I could be much more productive and contribute more to the company’s accomplishments.” This way the interviewer will know you’ve realized your mistake and are trying to correct it. Lack of plans for the future Sharing with the interviewer that you have no idea where you’ll be 5 years from now is likely to be interpreted as: “I don’t care about my future or your company.” If you make that mistake, offer an explanation: “Before setting goals, I’d like to acquire the skills necessary to help your company reach its long-term goals and stay ahead of the competition”. That will show that you are ambitious, but you won’t leave the company in the next few years. Not knowing the answer Hiring managers are aware that you can’t possibly have an immediate answer to all questions. Nevertheless, openly stating you don’t know the answer during an interview leaves you in a vulnerable position. So how do you recover from that? Say “This is an intriguing question and I need more time to think. May I take a few hours to consider it and send you the answer?” If the interviewer accepts your proposal, research the question thoroughly and make sure you deliver the answer within the agreed time frame. In Conclusion As a final takeaway, having a positive attitude is extremely important, especially if you’ve remained unemployed for a longer period. Companies want positive and competent people on their team, so find a way to keep your head up and exude confidence. If you want to check out more data architect interview questions, follow the link to our all-comprising article Data Science Interview Questions . Data Science Interview Questions However, if you feel that you lack some of the essential skills required for the job, check out the complete Data Science Program . In case you aren’t sure you want to turn your interest in data science into a full-fledged career, we also offer a free preview version of the Data Science Program . You’ll receive 12 hours of beginner to advanced content for free. It’s a great way to see if the program is right for you. complete Data Science Program free preview version of the Data Science Program