Sql coding interview questions for data engineer

Sql coding interview questions for data engineer

94. Data engineering aids in the transformation of raw data into useful information. Take-home SQL task or tasks. May 30, 2024 · 2. Pyspark architecture , RDD, map, flatmap, mapvalue. Hone your problem-solving skills by tackling data-related problems, and make sure to highlight these skills during the interview. May 28, 2024 · Typically, these questions will test concepts like string manipulation, data munging, statistical analysis, or ETL process builds. Helpful. Technical Interview. Please refresh. Assuming we have a database table tracking all purchases, your task is to write a SQL query to identify users who've Dec 22, 2023 · The FAANG interview process, notorious for its rigor, uses SQL questions as a litmus test to gauge a candidate’s ability to not only code but think logically and creatively under pressure. e. Explain the basic principles of BFS and DFS algorithms, including their traversal order and applications in various problem domains. Answer: To find the second-highest salary in a table, you can use a subquery with the LIMIT clause: SELECT DISTINCT salary. GROUP BY Dec 11, 2023 · 15 Common SQL Coding Interview Questions and Answers [2024] SQL skills are in high demand for data-related roles, making SQL coding interview a common step in the hiring process. 3 coding questions were given and 6 to 8 sql queries were asked to write on notepad. Advanced Joins: Self-joins, cross joins. A Spark module for processing structured data is Spark SQL. Amazon Data Engineer Coding Interview Questions. In projects, we use tools to manage changes so that everyone is on the same page, and updates don’t cause chaos. Understanding of APIs and Data Retrieval Methods. A data structure is a specialized format for organizing, processing, retrieving and storing data. I interviewed at Expedia Group (Bengaluru) in 11/1/2021. May 9, 2024 · It was conducted online, took almost a month to get to the final round, recruiter was very supportive, Total 3 rounds, 2 technical, 1 HR. The information gathered from numerous sources is merely raw information. Practice these tasks: Design an ETL pipeline; Create, modify, and manage sample databases; Look up sample coding challenges in C++, Python, or Scala and try solving them; Learn what typical SQL interview questions to expect; What are the SQL skills for SQL Interview Questions at a Glance. Sql A schema will be given. Assume that Snowflake, a cloud-based data-warehousing company, wants to identify its power users. Using the following SQL table definitions and data, how would you construct a query that shows…. playerid group by players. Here are the top 5 most commonly asked interview questions. , User Defined Function), which is used to expand PySpark's built-in capabilities. Apr 28, 2024 · I interviewed at EXL Service (Jersey City, NJ) 1st round: Live SQL Coding + GCP Multiple choice questions - Total 4 questions, 2nd round: Python, GCP, SQL, Spark questions with discussions on past projects and technologies. May 29, 2024 · Based on the computations from Glassdoor data, the average data engineer salary at Meta is 49% higher than the estimated average salary of a data engineer in the US. 3. Data Structures and Algorithm: 1 hr 3 questions : Leetcode medium 2. Application and Screening. Sample interview questions using SQL Join is explained with simple inner and outer joins as well as with tricky self-join examples. 1 Answer. . 60 min of SQL and Python (30 min and 3 View answer. If there are 10 records in the Emp table and 5 records in the Dept table, how many rows will be displayed in the result of the following SQL query: Select * From Emp, Dept. Q24. Feb 19, 2024 · DE Academy prepares data engineers for the challenges and Microsoft Data Engineer Interview Questions. They are identified as 'whale users'. Jun 28, 2021 · Below, we’ll explore some of the skills and knowledge you’ll need to excel in your new career and some of the most commonly asked Data Engineer interview questions. Advanced Modelling Data engineers need to be able to Apr 11, 2024 · Step 1: Take a new system; create a new username and password. Overall, SQL is a query language that communicates with databases. A data warehouse is a type of data management system that contains large volumes of data and can be used to perform queries or data analytics. SQL has become a common skill requirement across industries and job profiles over the last decade. If you're looking for an overview, we've compiled some top tips below: For beginners. Each row of the table is attached to itself and all other rows of the same table in a self-join. Question: Explain the concept of surrogate keys in a database. Star Schema: Design Focus: Designed for data warehousing and analytical processing. Define a SQL term. Mar 20, 2020 · A data science interview consists of multiple rounds. Python and sql coding questions for 1 hr. In this article, we cover 70+ SQL Interview Questions with answers asked in SQL developer interviews at MAANG and other high-paying companies. So read up on postgres. Apr 13, 2024 · The interview process for the IBM Data Engineer role involves a well-thought-out and structured hiring procedure. Mostly questions were from python, sql and pyspark. Jun 11, 2024 · Here, we will cover 45+ MySQL interview questions with answers that are commonly asked during interviews for Data Analyst and Data Engineer positions at MAANG and other high-paying companies. Name and Explain Some Common Aggregate Functions. Jan 22, 2024 · SQL Question 1: Average Post Hiatus. T-SQL adds a number of features that are not available in SQL. player_id) select teamid, playername, max_score from (select team_id, player_name, gamescore as Nov 29, 2023 · Generally speaking, the easier, definitional questions will be fewer and less important than the live coding questions—something to keep in mind as you prepare. I’ll post answers to May 13, 2024 · Easy questions in SQL interviews test your ability to perform basic aggregations like using COUNT or HAVING, if you can use basic joins or date-time manipulations. playerid = scores. You will be assigned 1 or 2 problems to solve within a stipulated amount of time. bottom 3 products. Oct 9, 2022 · Answer: I want to gain experience working with a variety of data sources and technologies. The question only tells us to sort records in ascending and descending orders. Data engineering helps in the transformation of unusable data into useful information. Write a function to sort an array so it produces only odd numbers. If you're aspiring to Jun 12, 2024 · Follow the following steps in order to deploy a big data solution. 10. The first step is to submit your application online at the IBM careers portal. Assume you have a table named "Sales" with columns "ProductID," "ProductName," and "SalesAmount. Interviewers want to know about you and why you want to become a data engineer. 1) Integrate data using data sources like RDBMS, SAP, MySQL, Salesforce. Apr 4, 2023 · Interactive SQL queries are frequently used by data scientists, analysts, and users of general business intelligence to explore data. If you are planning to apply for any of the data science positions or the positions of business analyst, business intelligence engineer 28 Top Data Scientist Interview Questions For All Levels. From my experience the process is the following: 1) call with recruiter (15-30 min) 2) tech screening (60 min with live coding in SQL and Python) 3) onsite interview (data modelling, behavioral questions) Interview questions [1] Question 1. After you successfully pass it, there’s another round: a technical one. Yes. Write a query that identifies the largest difference in total score of all assignments. Before applying to your new job as a Data Engineer, you’ll need to acquire key skills. This article will… May 30, 2024 · Technical round 1 Tested on coding capabilities and sql queries. May 25, 2024 · I interviewed at TCS (Hyderābād) Interview. Query to Find the Average Salary from an Employee Table: 2. Familiarity with Python Libraries like Pandas, NumPy, and PySpark. To help prepare, check out the Khan Academy SQL Course. What is Data Engineering? The application of data collecting and analysis is the emphasis of data engineering. This means that you need to evaluate applicants’ abilities accurately and objectively during the recruitment process, without bias. 2) Store data extracted data in either NoSQL database or HDFS. Question: Identify duplicate rows in the employees table based on employee_name. Database Design. We delve into not just the technicalities but also the strategic mindset required to excel in these roles. Step 3 : Add ssh public_rsa id key to the authorized keys file. Companies like Amazon and Google will often demand that the Jun 11, 2024 · Answer: Versioning is like keeping track of different editions of a book. Jan 15, 2024 · Below are the 200 Interview questions on Apache Spark using Python, but This is just a list of questions! You can read all of my blogs for free at : thebigdataengineer. Save. Jun 11, 2024 · around 5-6 rounds in total, with most of the interviews done in chinese / english. Our article offers an in-depth look into the questions that shape the future of data engineering at Microsoft. This Box interview question asks you: “You are given a table containing assignment scores of students in a class. average of $41kyear base pay. Aug 15, 2022 · This python data engineer interview question has one table with 4 fields. Apr 12, 2021 · Here is a post with a comprehensive list of the most asked SQL interview questions along with the answers. For any organization that works with big data extensively, hiring skilled data engineers is a must. Mar 18, 2024 · Here are general, process, and technical questions interviewers may ask you during a data engineer interview. It’s true. Given a table of Facebook posts, for each user who posted at least twice in 2024, write a SQL query to find the number of days between each user’s first post of the year and last post of the year in the year 2024. Data Modeling. Apr 12, 2024 · The BP interviewer may ask this question to evaluate your knowledge of algorithms commonly used in data processing and analysis tasks as a data engineer. Jan 29, 2024 · 5 SQL Interview Questions for Amazon BIE. Given two nonempty lists of user ids and tips, write a function called “most tips” to find the user that tipped the most. Mar 8, 2020 · SQL is one of the most essential programming languages for data analysis and data processing, and so SQL questions are always part of the interview process for data science-related jobs, such as data analysts, data scientists, and data engineers. Alright. Your role will involve designing a database for tracking ML jobs running on the platform. Amazon Data Engineer Interview Questions In this guide, I'll provide comprehensive insights into the Amazon Data Engineer interview process, including common questions you might encounter, tips on interview preparation, and the qualities Amazon seeks in an ideal candidate. Apr 13, 2024 · These include two ETL rounds focusing on SQL and Python/Java coding, a data modeling round where candidates are tested on their ability to design data models based on business scenarios, and a behavioral round. In this post, we have outlined the most frequently asked questions during the statistical and machine learning, analysis, coding, and product-sense interview stages. " Jun 7, 2024 · Self-join is a type of join that can be used to connect two tables. Design and build a data warehouse for managing inventory. managerial round. Assume a schema of Emp ( Id, Name, DeptId ) , Dept ( Id, Name). FROM employees. Mar 14, 2023 · Most asked SQL interview questions in Data Engineering Interviews (Part I) SQL (Structured Query Language) is a programming language used to manage relational databases. Redshift, Redshift Spectrum, Athena for Analytics, and Kinesis Stream Analytics (or something) for real-time streaming SQL. Apr 14, 2021 · Being a position in the data science field, it should come as no surprise that SQL is another vital skill for data engineering. Coding is an important skill that interviewers evaluate at data engineer interviews. Top 3 products vs. I interviewed at Lyft (San Francisco, CA) in 7/1/2020. Location also plays a part in the difference in salary based on Glassdoor data. Below are a few data engineer interview questions on SQL concepts, queries on data storage, data retrieval, and a lot more. Phone screen: 1 hr Sql - 3 Questions (25 mins) and Coding - 1 question (25mins) Onsite: 1. 3 rounds are there: 1. Answer Question. Aug 30, 2023 · This python data engineer interview question has one table with 4 fields. Data Engineer skills. Dec 8, 2023 · The Amazon Data Engineering interview can be broadly divided into 3 rounds. SQL Queries and Database Operations. Throughout this article, we'll explore a range of SQL interview questions and answers for practitioners at the beginner and intermediate levels. SQL proficiency is a valuable asset for data analysts and data scientists, and excelling in SQL interviews can be a game-changer for your career. Solution. If there are users with the same email activity, then rank those users alphabetically. Feb 2, 2024 · Understanding Spark through interview questions is a need for any data expert who wants to get a position as a Spark data engineer. Here is a list of skills and qualifications commonly sought after for data engineering roles: Technical skills. Photo from Pexels. Athena is Presto, which is very similar to postgres. live SQL coding as well as spark concept questions. 1. It typically involves live coding and the purpose is to check if a candidate can program and May 30, 2024 · Below are some sample Amazon data engineer interview questions. Programming Languages: Proficiency in languages commonly used in data engineering, such as Python, Java, or Scala. This article will… A curated list of 230 SQL & Python coding questions and solutions. com. These questions often extend beyond the realm of basic query writing; they probe into areas of query optimization, complex joins, data aggregation, and the Jan 26, 2024 · SQL Question 4: Database Design for Databricks Machine Learning Jobs. As a result, a self-join is mostly used to combine and compare rows from the same database table. Dec 12, 2023 · By mastering these five advanced SQL interview coding questions and understanding the underlying concepts, you’ll be well-prepared to showcase your SQL expertise to potential employers. BECOME A DATA ENGINEER. This includes procedural programming elements and a local variable to provide more flexible control of how the application flows. Free SQL Tutorial for Beginners – Download PDF. 55 data engineering interview questions (+ sample answers) to hire top engineers. To compare: Meta Brazil Data Engineer: est. test also included 30 MCQs on java and SpringBoot. 2) Determine where along the hierarchy of each dimension the information will be kept. Jan 24, 2024 · SQL Question 1: Identify IBM's High Capacity Users. We need to find the email activity for each user and then rank all the users based on their email activity in the descending order. May 13, 2024 · Interview. Concepts like Resilient Distributed Datasets (RDDs) need to be mastered in the context of data manipulation, showcasing light features like fault-tolerance with parallel processing capabilities. Oct 27, 2020 · This type of interview question is also at the typical SQL knowledge level expected for fresh graduates embarking on data engineers' careers. We need to arrange records based on names (text values) in two columns. In order to get interview-ready, make sure to practice a whole bunch of problems on the following topics: Arrays, strings, and linked lists; Sorting algorithms — quicksort, merge sort, heap sort, etc. This course discusses 15+ commonly asked interview questions for a data analyst job. SQL and GCP heavy interview. Hence they want to be absolutely certain that their employees know SQL in depth. How you apply patterns to solve problems at the interview and your ability to think out solutions with an analytical approach will put you ahead of the competition. A data engineer needs to be able to construct and execute queries in order to understand the existing data, and to verify data transformations that are part of the data pipeline. Jun 11, 2024 · By executing queries, SQL can create, update, delete, and retrieve data in databases like MySQL, Oracle, PostgreSQL, etc. Explore the top data science interview questions with answers for final-year students and professionals looking for jobs. A power user is defined as any user who runs at least 500 query requests per month. Coding is a key aspect of the data engineer interview. L. Apr 30, 2024 · The interview process was smooth. Feb 1, 2021 · Every company does things differently, but here are a few of the more common ways companies test SQL skills: In-person (or video) interview where you're asked SQL questions or given SQL problems to solve. Query to Find the Second Highest Sep 27, 2023 · The premise of this data engineer SQL interview question is fairly simple. This article demystifies the SQL interview process for Data Engineers, Apr 17, 2024 · Interview Questions for Data Engineers. Question. Jul 15, 2022 · Interview questions [1] Question 1. As tech companies, their business heavily relies on data. After qualifying that I gave the interview which consists of questions like Reverse a linked list and basic sql questions and my project experience which I answered quite comfortably . Overall, it was a easy to medium round. gamescore) as gamescore from players join scores on players. You will always get SQL interview questions with a little twist. Aug 14, 2023 · Data engineering often involves overcoming intricate challenges related to data quality, scalability, and performance. Hacker Rank Test (mostly on sql) 2. IBM always recommends that you join their Talent Network when Nov 2, 2020 · Photo by Clément H on Unsplash Programming. When we add items over capacity we free up space by removing an item first: 1) remove any expired item first 2) If there are no expired items, find the items with the lowest priority number, and remove the one Nov 15, 2023 · Question 10: Find Duplicate Rows. The ETL rounds simulate Meta’s standard ETL tasks, assessing the candidate’s skills in handling data engineering tasks. coding round (medium level leetcode question) you have to solve the question and dry run it 3. Q6. Mar 27, 2022 · I applied online. 2. Didn't pass the tech screening. Write sql queries to check if the row is primary column. mediumamazon. If you’re interviewing for a data analyst role, chances are you know what SQL is (and your interviewer assumes you know this). Explain the concept of query optimization in SQL with examples. 3 answers I was asked this. Database and system design is another crucial skill for any data engineer. Star-Schema vs 3NF vs Data Vault vs One Big Table - 🏷️ Basic. Relational Database Management is an important part of Data Science and SQL is the most-used language in data science, according to the 10,000+ data professionals who responded to StackOverflow's 2020 survey. 3) Deploy big data solution using processing frameworks like Pig, Spark, and MapReduce. Question: Find the Second Highest Salary. Hello, I am a data engineer with 4 years of experience I am currently prepping to switch jobs what are some coding questions I can expect apart from…. SELECT employee_name, COUNT(employee_name) AS count. Apr 11, 2024 · Questions addressing data modeling and database architecture test your understanding of entity-relationship modeling, normalization and denormalization, dimensional modeling, and relevant ideas. Here comes the most unpleasant part of all software engineering interviews: the coding interview, where you are asked to implement complex algorithms (that you will probably never need at work) using the most efficient data structures in the fewest lines of code possible and explain the time and space complexity of your code, all within 30 Sep 27, 2023 · Having a good grasp of the following concepts will help you better understand the questions and answers: Basic Python Syntax and Structures. mostly window functions for sql. All you need is the perfect preparation. Hard. General questions. SQL is a query language to operate on sets. Four important concepts from SQL and dataframe questions from Python are discussed. google_gmail_emails. Additionally Feb 12, 2024 · 15 Common SQL Coding Interview Questions and Answers [2024] SQL skills are in high demand for data-related roles, making SQL coding interview a common step in the hiring process. most of the interviewers were quite friendly and nice. Jun 30, 2021 · 5. System design (low level) : about oops concept proper implementation of classes. Code a data structure which allows us to store and retrieve items by key up to a fixed capacity. The most important aspect of Spark SQL & DataFrame is PySpark UDF (i. Oct 30, 2023 · How do you prepare for an SQL data engineer interview? You prepare with one word: practice. You have a flights table that contains information about all the flights an airline has booked. Jan 10, 2024 · 13. 11. playerid as playerid, player_name, team_id, score_id, max (scores. Databricks is a leading data analytics platform that also offers robust machine learning capabilities. HackerEarth is a global hub of 5M+ developers. Some medium Python coding questions include: 12. It offers the DataFrame programming abstraction and functions as a distributed SQL query engine. Apr 17, 2024 · Knowing these questions will boost your confidence and give you an edge for landing a dream job. It went well and easy process and hassle free. The good news is that you don’t need to undertake a traditional SQL Question 1: Identify VIP Users in Snowflake. Available engines: PostgreSQL, MySQL, Python and R. They're often the professionals who design, construct, and manage scalable data infrastructures working alongside Data Science, Engineering, and Product teams. Technical interview questions for Amazon are mostly related to coding, algorithms, and machine learning. Include the product name, sales amount, and any other relevant details. Here’s a step-by-step guide on what you can expect: 1. Transactions: ACID properties. 4 set of rounds conducted 1. There would be two main entities - Jobs and Users. TODO; SQL SQL is a domain-specific language used in programming and designed for managing data held in a relational database management system (RDBMS). Apr 15, 2022 · Python Coding Interview Question #1: Class Performance. As one of the world's largest tech companies, Amazon is continuously seeking top talent. Apr 9, 2024 · Get FREE Access to Data Analytics Example Codes for Data Cleaning, Data Munging, and Data Visualization. SQL interviews are meant to evaluate candidates’ technical and problem-solving skills. May 25, 2024 · Interview had Hackerrank round containing 3 coding medium coding questions followed by technical discussion. I was also asked the project of my current company. In SQL, an aggregate function uses the data from multiple rows to calculate a single result. Step 2 : Install SSH and with the master node setup SSH connections. In IBM, a crucial part of user base are high-volume purchasers, who buy IBM products or services frequently and in large quantities. And where there is data, there is SQL which the FAANG companies often use. Instructions: Write a query to return the top 3 and bottom 3 products in August 2021 ranked by sales. Output the user and number of the days between each user's first and last post. Common aggregate functions include COUNT (returns the number of rows), SUM (returns the sum of all values in that column), AVG (returns the average value), MIN (returns the smallest value) and MAX Sep 15, 2021 · The main reason is their SQL interview questions are a bit different. Step 4 : Add the new DataNode hostname, IP address, and other details in /etc/hosts slaves file: May 21, 2024 · The data generated by various sources is simply raw data. Write an SQL query to retrieve the top N products based on their total sales. 2 days ago · I interviewed at Meta. But it will be tough in the job. Nov 16, 2022 · Amazon data engineer interview questions: Coding. All questions will be based on that. A ubiquitous interview challenge for data engineering roles is being asked to do some data warehousing. SQL query optimization aims to improve query performance by selecting the most efficient execution plan. TSQL is a proprietary procedural language used by Microsoft in SQL Server. More often than not, there is one more data engineer technical interview with a hiring manager (and guess what - it involves some more coding!). Jan 23, 2024 · These questions assess the candidate's in-depth knowledge and expertise in SQL development, database design, optimization, and advanced SQL concepts. This article on Top 200 Data Engineer Interview Questions & Answers 2024 will help you with details on Essential Data Engineering Interview Questions. Apr 11, 2024 · The data engineer interview process will usually start with a phone screen, followed by 4 technical interviews (expect some coding, big data, data modeling, and mathematics) and 1 lunch interview. 2 technical rounds asked about spark and databricks and SQL queries and also ADF questions scenario based pyspark coding questions also some questions on project and the works we did in project. Data Structures like Arrays, Lists, and Dictionaries. Interview questions [1] Question 1. Data Modeling: Normalization, schema design. Complex Queries: Subqueries, CTEs. "with var1 as (select players. As a matter of fact, data engineering candidates may find that they need to complete two different technical interviews, one for SQL and another for other coding skills. Awesome SQL; Data visualization tools/BI; Tableau Oct 20, 2023 · In this article, we’ll cover the top 15 SQL coding interview questions, along with detailed explanations and code examples. Solve from more than 2000 coding problems and interview questions on 100+ different topics. The aim is to identify these power users so that special care can be taken to ensure their needs are being met and May 17, 2023 · As a data engineer, in addition to your standard LeetCode like programming problems, companies will ask you to solve question using SQL. Core Technical Skills — deepen your understanding of SQL, Python, and ETL processes. With data driving decision-making, skilled Data Engineers are in high demand, intensifying the interview process. General data engineer interview questions. May 22, 2023 · The process took 1 week. However, since values are text, it means we need to order rows alphabetically. Be well-versed in data modeling concepts. I also want to learn how to design and implement efficient and scalable data architectures. Just go and apply as you like. 5. Explain PySpark UDF with the help of an example. 2 rounds 1 is coding and another is data modeling. And understand the database offerings of Amazon itself: - SQL: RDS, Aurora for operational databases. One of the engines in Aurora is Postgres. Answer: Surrogate keys are like giving each student in a class a unique ID. Candidates then proceed to the second round, which is a technical phone interview, with questions focusing on SQL and Data Modeling. Example. As a data engineer… Oct 12, 2023 · The main reason is their SQL interview questions are a bit different. Oct 4, 2023 · By mastering these five advanced SQL interview coding questions and understanding the underlying concepts, you’ll be well-prepared to showcase your SQL expertise to potential employers. How to Answer. Follow along and check the 23 most common and advanced SQL Interview Questions Data Scientists and Machine Learning SQL. Write a function to find non duplicate numbers in the first list and preserve the order of the list: [1,1,3,2,5,6,5] --> [1,3,2,5,6] Given a list, return the numbers which have maximum count. In-person (or video) live coding session where you're asked to use SQL skills to answer questions in real time. First they told me to appear for an AMCAT test which consists of Logical Reasoning, Verbal Ability ,Aptitude and Coding Rounds. 6 days ago · Commonly Asked Azure Data Engineer Interview Questions With Answers 1. Both the rounds were of 30 minute duration. One of such rounds involves theoretical questions, which we covered previously in 160+ Data Science Interview Questions. System Design — practice designing robust data pipelines and architectures, often a critical component of the interview. We help companies accurately assess, interview, and hire top developers for a myriad of roles. As a result, it is a unary relationship. Data engineering is a technical role, so while you’re less likely to be asked behavioural questions, these Nov 29, 2023 · A: For effective data engineer interview prep, we recommend focusing on three key areas: 1. Performance Tuning: Query optimization. Can you integrate cloudera with data bricks. Select all entries from the flights table. May 3, 2024 · There are 4 rounds 1st Round - Interview with HR and they want to access if you are a good fit for the role or not & possess the skills 2nd Round - Coding round with a Manager (typically SQL) 3rd Round - Coding Part2 ( Again SQL, Some Python Questions, Cloud Questions) 4rd Round - Final Interview with Partner and Director. SQL is the most important skill for a data scientist. Whether you are a fresher or an experienced professional with 5 , 8 , or 10 years of experience, this article gives you all the confidence you need to ace Introduction The role of a Data Engineer is crucial. After applying for the job, a screening round is conducted, which is a telephonic interview with a recruiter. Mar 29, 2024 · Coding interview Questions Asked at Data Engineer Interviews. Hint. SQL (Structured Query Language): Proficient in writing complex SQL queries for data analysis and manipulation. Dec 9, 2023 · 1) Determine which dimensions will be included. Interview. tj mp tt ed br js zf vx vy de