Snowflake
Cloud data platform enabling data warehousing, data lakes, and data sharing.
4 Rounds
~21 Days
Hard
The Interview Loop
Recruiter Screen (30 min)
Standard fit check, behavioral questions, and resume overview.
Technical Loop (3-4 Rounds)
Deep dive into domain knowledge, coding, and system design.
Interview Question Bank
Data Engineer
•
Behavioral
•
medium
Tell me about a time you had to optimize a highly inefficient data pipeline. What was the root cause, what steps did you take to fix it, and how did you measure the impact?
#Ownership
#Optimization
#Impact
#Problem Solving
Data Engineer
•
Behavioral
•
medium
Describe a situation where you strongly disagreed with a senior engineer or architect about the design of a data model. How did you communicate your concerns, and what was the resolution?
#Conflict Resolution
#Communication
#Teamwork
#Data Modeling
Data Engineer
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Coding
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medium
Write a Python function to merge overlapping time intervals for user sessions. Given an array of intervals where intervals[i] = [start_i, end_i], merge all overlapping intervals and return an array of the non-overlapping intervals that cover all the intervals in the input.
#Arrays
#Sorting
#Intervals
#Python
Data Engineer
•
Coding
•
hard
Given an array of daily stock prices, find the maximum profit you can achieve with at most two transactions. You may not engage in multiple transactions simultaneously (i.e., you must sell the stock before you buy again).
#Dynamic Programming
#Arrays
#State Machine
Data Engineer
•
Coding
•
medium
Implement a rate limiter in Python that allows a maximum of N requests per minute per user. The function should return True if the request is allowed, and False otherwise.
#Hash Maps
#Queues
#Concurrency
#System Design Basics
Data Engineer
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System Design
•
hard
Design a near real-time data ingestion pipeline using Snowpipe and AWS S3 to handle 10TB of daily log data. How do you handle deduplication, schema evolution, and error notifications?
#Snowpipe
#AWS S3
#Data Ingestion
#Deduplication
#Schema Evolution
Data Engineer
•
System Design
•
hard
Design a Change Data Capture (CDC) system from an operational PostgreSQL database into Snowflake. Ensure exactly-once processing and minimal impact on the source database.
#CDC
#Debezium
#Kafka
#Snowflake Streams
#Snowflake Tasks
Data Engineer
•
System Design
•
hard
Design a data lineage tracking system that parses incoming SQL queries to build a dependency graph of tables and views. How would you store and query this graph?
#Data Lineage
#Graph Databases
#Metadata Management
#Query Parsing
Data Engineer
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Technical
•
medium
Given a table with a VARIANT column containing deeply nested JSON payloads from a web tracking system, write a Snowflake SQL query to flatten the JSON, extract the 'user_id' and 'event_type', and handle cases where the 'event_type' key might be missing or null.
#VARIANT data type
#FLATTEN function
#Semi-structured data
#JSON parsing
Data Engineer
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Technical
•
hard
Explain how Snowflake's micro-partitioning works. If you have a table with 50 billion rows queried mostly by 'transaction_date' and 'tenant_id', how would you choose a clustering key, and how does Snowflake maintain it?
#Micro-partitions
#Clustering Keys
#Performance Tuning
#Storage
Data Engineer
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Technical
•
hard
Write a SQL query to implement a Type 2 Slowly Changing Dimension (SCD2) update. You have a source staging table and a target dimension table. Use a MERGE statement to insert new records, close out old records (update end_date), and insert the updated active records.
#SCD Type 2
#MERGE statement
#Data Warehousing
#ETL
Data Engineer
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Technical
•
medium
How does Snowflake's Time Travel feature work under the hood? Walk me through a scenario where a junior engineer accidentally drops a critical production table, and how you would use Time Travel to recover it.
#Time Travel
#Data Recovery
#UNDROP
#Storage Costs
Data Engineer
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Technical
•
medium
Given a table of 'employee_salaries' (emp_id, dept_id, salary), write a SQL query to find the top 3 highest paid employees in each department. Do not use subqueries in the SELECT clause.
#Window Functions
#DENSE_RANK
#CTEs
Data Engineer
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Technical
•
medium
Describe the difference between a Materialized View and a standard View in Snowflake. When would you use one over the other, considering compute costs and data freshness?
#Materialized Views
#Compute Costs
#Caching
#Performance
Data Engineer
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Technical
•
hard
You notice that a Snowflake Virtual Warehouse is queuing queries during peak morning hours, causing SLA breaches. Walk me through your troubleshooting steps. How do you decide between scaling up vs. scaling out?
#Virtual Warehouses
#Concurrency
#Scaling
#Queuing
Difficulty Radar
Based on recent AI-sourced data.
Meet Your Interviewers
The "Standard" Interviewer
Senior EngineerFocuses on core competencies, system constraints, and clear communication.
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Think Out Loud
Always explain your thought process before writing code or drawing architecture.