Databricks Interview Questions
We track 34 interview questions reported from Databricks: 23 in Coding & Leetcode-style Questions, 11 in System Design for ML. They average 3.5/5 difficulty — medium for a working engineer — and every one was reported by someone who sat the loop, not written by us. The topics that come up most: idempotency, dp, object-design, concurrency.
Practice these on the problems board →Question mix
- Coding & Leetcode-style Questions23
- System Design for ML11
Difficulty
- 2/5 — easy3
- 3/5 — medium13
- 4/5 — hard17
- 5/5 — very hard1
Asked for SWE (33), Infra (13), MLE (7), DataEng (2)
Topics Databricks asks about
Reported Databricks questions
SnapshotSet with Iterator
4/5Design a customized collection data structure that guarantees safe concurrent iteration, a classic engineering puzzle from Databricks interviews. The task requires building mechanisms to insert elements, verify membership, and generate isolated point-in-time views of the stored items without locking the entire system. This problem assesses your understanding of immutability, memory management, and thread-safe design patterns. The full problem and model solution require a subscription.
Coding & Leetcode-style Questionsdata structuresWeighted LRU Cache
3/5Tackle an advanced data structure challenge frequently featured in technical evaluations at Databricks, focusing on a specialized memory-bounded repository. Unlike traditional retrieval systems that measure capacity by item count, this variation assigns variable storage costs to individual entries, triggering sequential purging based on usage history when limits are exceeded. Successfully navigating this test demands rigorous state management and efficient algorithmic design. Access the complete problem description, complexity analysis, and optimal solution code through a paid subscription.
Coding & Leetcode-style QuestionscodingCloud Storage System (Online Assessment)
4/5This Databricks online assessment challenge asks engineers to architect an in-memory repository that manages hierarchical directory structures and data objects through progressively difficult tiers of functionality. Candidates must implement efficient routines for insertion, querying, deletion, and advanced administrative capabilities while maintaining strict execution speed and memory limits. The exercise tests data structure design, clean code architecture, and problem-solving adaptability under expanding requirements. To view the complete problem description and model solution, a paid subscription is necessary.
Coding & Leetcode-style Questionsonline assessmentImplement LazyArray with Deferred Function Execution
3/5In this coding challenge reported during Databricks interviews, applicants must build a specialized data structure that delays operations until a final trigger occurs, mirroring modern big data processing frameworks. The assignment assesses your understanding of deferred evaluation patterns, method chaining, and internal state management in custom collections. It probes how well you can architect modular, scalable code that optimizes execution timing. To view the comprehensive breakdown, test cases, and expert model solution, a paid subscription is required.
Coding & Leetcode-style Questionsfunctional programmingDesign a Scalable Ad Marketplace System
4/5Explore a large-scale ad marketplace system design problem commonly asked in Databricks engineering interviews, centering on real-time bidding, publisher-advertiser matching, and transactional financial controls. You will address high-concurrency challenges involving budget depletion limits, timezone-aware resets, and distributed state management across millions of daily requests. Access to the exhaustive system architecture guide, capacity estimations, and complete model solution requires a paid subscription.
System Design for MLadsbiddingbudget-accountingDesign a Payment Gateway System
4/5Designing high-throughput financial infrastructure is a pinnacle system design challenge, frequently discussed in architectural interviews at companies like Databricks. This scenario focuses on building a resilient payment gateway capable of validating point-of-sale card transactions while ensuring low latency and high availability. You must address intelligent request routing, issuer bank integration, and robust scaling strategies under heavy traffic loads. Access the complete system design guide and comprehensive architecture blueprint with a paid subscription.
System Design for MLpaymentsidempotencypci-dssHouse Robber: Linear, Circular, and Gap Variants
3/5This classic dynamic programming problem, featured in Databricks interviews, explores optimization strategies where selecting adjacent items is forbidden. You will need to determine the maximum cumulative value obtainable under strict exclusion rules. The exercise extends beyond the linear baseline into circular arrangements, hierarchical tree structures, and customized spacing constraints that significantly alter the state transitions. Unlock the complete breakdown and optimal algorithmic implementation by grabbing a subscription.
Coding & Leetcode-style Questionsdparraysspace-optimizationDistributed File System Metadata Layer with Strong Consistency
4/5Dive into a complex distributed systems architecture challenge inspired by technical interviews at Databricks. You will design the directory and file management metadata tier for a massive storage network, emphasizing strict consistency guarantees and fault tolerance over weak replication models. The exercise assesses your mastery of consensus protocols, hierarchical tree organization, and high-availability design principles. Unlock the complete system architecture blueprint and expert analysis with a subscription.
System Design for MLdistributed-systemsfilesystemstrong-consistencyLinear Regression via Gradient Descent (MSE)
3/5Practice fundamental machine learning implementation with this core optimization exercise reported from Databricks hiring rounds. You are asked to construct an iterative parameter estimation algorithm from scratch using standard loss metrics and gradient update rules without relying on pre-built machine learning libraries. This task gauges your mathematical intuition regarding convergence behavior, learning rate tuning, and gradient debugging. View the complete problem breakdown and optimal mathematical solution by securing a subscription.
Coding & Leetcode-style Questionsgradient-descentlinear-regressionnumpyStock Trading Agent Service with Order Deadlines
4/5This machine learning system design challenge, frequently encountered in technical interviews at Databricks, requires candidates to architect an intermediary proxy service connecting clients with an external brokerage. The core engineering obstacle involves managing high-throughput transaction requests tied to strict time expiration thresholds without relying on asynchronous webhook notifications. Participants must formulate robust polling strategies and concurrency controls to cleanly handle massive spikes of simultaneous cancellations. Access to the complete architectural blueprint, component interactions, and expert evaluation is locked behind our paid subscription.
System Design for MLidempotencyqueueingapi-integrationLazy Array with Deferred Map
3/5Reported from Databricks interviews, this design challenge asks you to build a collection wrapper that supports deferred, immutable transformations. You must record mapping operations without executing them immediately, delaying computation until a specific lookup method is invoked while ensuring separate transformation chains remain isolated. The problem evaluates your understanding of lazy evaluation, immutability principles, and clean class design. Access the complete problem description and optimal solution by subscribing.
Coding & Leetcode-style Questionsobject-designlazy-evaluationimmutabilityDesign a Slack-like Chat System with Deletion Semantics
4/5Designing real-time communication platforms requires handling complex state synchronization and deletion semantics across diverse client states. This reported Databricks system design question challenges you to architect a messaging network where conversation and message removals propagate reliably to both active and long-offline participants. You will explore distributed consistency models, synchronization protocols, and scalability trade-offs. Unlock the full design scenario and expert evaluation framework by purchasing a subscription.
System Design for MLmessagingsystem-designdeletionIn-Memory KV Cache with Write-Ahead Log
4/5Mastering systems architecture is crucial for tackling advanced engineering challenges reported in Datadog interviews, such as designing a robust caching layer with persistence guarantees. This architectural exercise tests your capability to architect a single-node memory store, implement write-ahead logging for crash recovery, and address horizontal scaling and concurrency hurdles. You must carefully balance memory management, disk durability, and synchronization overhead under heavy loads. Access to the comprehensive problem breakdown and model solution requires a subscription.
System Design for MLcachingpersistenceconcurrencyFile System Encryption Count and Minimum-Cost Encryption
3/5This Databricks interview question invites you to navigate a hierarchical file system tree to compute security statistics and optimize encryption overhead. The first part tests your recursive tree traversal capabilities, while the second part explores optimization strategies for minimizing operational costs across nested directories and individual files. It is an excellent exercise for practicing dynamic programming and greedy choices on tree structures. To view the comprehensive problem description and optimal model solution, a subscription is required.
Coding & Leetcode-style QuestionstreedprecursionStreaming RLE + Bit-Packing Encoder/Decoder
3/5Tackling data compression challenges efficiently is a common theme in technical interviews, as seen in this Databricks coding problem. Candidates are asked to construct a specialized streaming encoder that dynamically switches between run-length encoding and bit-packing strategies depending on the incoming integer sequence characteristics. This exercise evaluates your understanding of memory layouts, lazy evaluation through iterators, and edge cases involving extreme numeric bounds. To explore the complete problem description and review a fully optimized model solution, a subscription is required.
Coding & Leetcode-style QuestionscompressionstreamingiteratorIn-Memory Revenue Tracker with Referral Attribution
3/5Designed around Databricks engineering interviews, this problem challenges candidates to build an in-memory revenue tracking platform with built-in referral attribution. The exercise tests data modeling skills for handling hierarchical relationships, where incoming revenue from referred users partially benefits their referrers. Developers must design efficient APIs and internal structures to handle rapid updates and aggregated balance queries. Access to the full problem specifications and a production-grade model solution requires a paid subscription.
Coding & Leetcode-style Questionsobject-designhashmapattributionDelete Element at Flattened Index From Sorted Intervals
2/5Manipulating compressed range structures based on sequential indices is a classic algorithmic hurdle frequently encountered during technical evaluations at prominent data infrastructure firms like Databricks. This problem tests your ability to translate abstract position lookups into precise segment manipulations, handling boundary conditions where targeted values cause ranges to split or contract. Success demands careful pointer management and efficient searching techniques to operate within strict performance boundaries. Unlock the complete problem guide, edge-case analysis, and fully tested reference solution by upgrading your account today.
Coding & Leetcode-style Questionsintervalsbinary-searchmathThread-Safe Durable Log Writer
4/5Design a robust concurrent logging utility that guarantees data persistence to disk under heavy multithreaded contention, reflecting a challenging concurrency scenario from Databricks interviews. This problem tests your mastery of synchronization primitives, blocking mechanisms, and operating system disk synchronization guarantees to ensure durability against unexpected crashes. You must carefully manage thread ordering while enforcing strict synchronization barriers before write operations return. The full problem statement, architectural review, and robust reference solution require a subscription.
Coding & Leetcode-style QuestionsconcurrencydurabilityfsyncFastest Commute Mode Through a Grid
3/5Encountered in a Databricks interview, this pathfinding puzzle challenges you to navigate a matrix containing various transportation types, each carrying distinct time and financial tolls, while locating the quickest journey between starting and ending points. The problem evaluates advanced graph search algorithms and tie-breaking logic. The full problem and model solution require a subscription.
Coding & Leetcode-style Questionsdijkstragridshortest-pathSQL Query Plan Optimizer With Predicate Pushdown
5/5This Databricks interview question challenges you to build a relational query plan optimizer capable of executing predicate pushdown transformations. You will work with a tree structure of query operators like scans, filters, and joins, ensuring that rewritten plans remain fully evaluable and semantically correct. This advanced problem evaluates deep architectural thinking, AST manipulation, and optimization theory. Access to the complete problem description and an optimal model solution requires a subscription.
Coding & Leetcode-style Questionsquery-optimizationtreessqlDesign a Waymo-like Autonomous-Vehicle Ride-Hailing App
4/5Design a robust ride-hailing application powered by autonomous vehicles, modeled after leading industry platforms like Waymo, during this advanced Databricks system design interview. This challenge tests your capability to orchestrate complex user lifecycles, real-time vehicle matching algorithms, and continuous geographical tracking while handling unpredictable real-world disruptions such as network failures or sudden cancellations. You must formulate scalable microservices, efficient state management, and fault-tolerant data flows to ensure safe and reliable transit operations. Unlock the complete system architecture, detailed component deep-dives, and comprehensive design patterns with a subscription.
System Design for MLride-hailinggeospatialmatchingFirst Index of an Anagram Substring
2/5Tackle the string manipulation puzzle of locating the earliest occurrence of a permuted pattern inside a larger text. This Databricks interview question assesses your proficiency with sliding window techniques, frequency counting, and efficient substring scanning. You will need to design an approach that tracks character distributions dynamically to pinpoint matching segments without resorting to sluggish brute-force checks. The complete problem description and clean implementation walkthrough are available exclusively to subscribers.
Coding & Leetcode-style Questionssliding-windowstringshashmapImplement a Thread-Safe Circuit Breaker
3/5This concurrency design question commonly featured at Databricks tests your understanding of resilient system architectures. You are tasked with developing a synchronization mechanism that manages operational states to prevent cascading failures when communicating with unstable external dependencies. This evaluates your command over multithreading safety, state machine transitions, and timing logic. Unlock the complete technical specifications and robust reference implementation with an active subscription.
Coding & Leetcode-style Questionsstate-machineconcurrencyresilienceSnapshot Set / MVCC Iterator
3/5Designing custom data structures with historical consistency is a classic challenge often encountered in systems design interviews at companies like Databricks. This problem tests your capability to implement a collection that supports multi-version concurrency control, allowing users to capture immutable state snapshots and traverse historical data points without interference from subsequent modifications. It assesses deep understanding of state management and memory efficiency. To unlock the comprehensive editorial, architectural patterns, and complete implementation, a subscription is required.
Coding & Leetcode-style Questionsdata-structuresnapshotmvccMaximal Square and Maximal Rectangle in Binary Matrix
3/5Explore a classic two-dimensional matrix analysis challenge commonly asked by Databricks, focusing on identifying maximal uniform regions within binary data grids. This problem tests your ability to apply dynamic programming principles efficiently to compute the largest square and rectangular boundaries composed entirely of matching elements. Candidates must optimize spatial memory usage and runtime complexity while evaluating subgrid states. Access the complete problem description, analysis, and clean model solution through our subscription plan.
Coding & Leetcode-style Questionsdpgridmonotonic-stackGeneralized M×N Tic-Tac-Toe with Win Length K
2/5Reported during interviews at Databricks, this object-oriented design challenge requires you to build a flexible, generalized version of Tic-Tac-Toe on a custom grid with a variable winning sequence length. The exercise tests your ability to manage state changes, track turns, and implement robust win-detection algorithms across rows, columns, and diagonals for boards of arbitrary dimensions. Unlock the complete problem prompt, interactive methods, and production-ready solution by subscribing today.
Coding & Leetcode-style Questionsobject-designgridsimulationMinimum Substring Partition Covering Target String
4/5Analyze a complex string parsing challenge that requires reconstructing a target sequence using the fewest possible continuous segments from a source text, frequently asked during technical evaluations at Databricks. This problem evaluates your advanced string processing, greedy algorithms, and dynamic programming skills to find optimal index ranges under strict constraints. You will also consider dynamic modifications and edge cases where coverage might fail. The complete problem statement and optimized solution are available exclusively with a paid subscription.
Coding & Leetcode-style QuestionsstringsdpparsingBook Seller External Fan-Out Broker Service
4/5This distributed systems design interview question from Databricks asks you to architect an external fan-out broker service that queries dozens of third-party APIs concurrently to find the best price for customers. You will need to address high-scale concurrency, asynchronous communication, timeout handling, and fallback pricing logic within a robust architecture. The scenario evaluates your capability to build resilient systems that depend on external, unreliable services. The full architectural breakdown and expert solution require a subscription.
System Design for MLfan-outidempotencycircuit-breakerJob Scheduler with Task Dependencies (DAG Executor)
4/5This Databricks system design question requires you to architect a robust low-level job scheduler capable of executing tasks based on directed acyclic graph dependencies. You will need to address complex architectural concerns including topological sorting, lifecycle state management, worker allocation, heartbeat mechanisms, and failure recovery policies. It evaluates your ability to design reliable, distributed concurrent systems. Unlock the complete problem overview and expert solution with a subscription.
System Design for MLschedulingtopological-sortdagUniformly Sample a Minimum Spanning Connection of Groups
4/5As a challenging problem reported from Databricks engineering interviews, this task requires connecting multiple disjoint graph components using the absolute minimum number of edges while ensuring a uniform probability distribution across all valid spanning configurations. The problem evaluates advanced graph theory concepts, random sampling algorithms, and combinatorial awareness. Mastering this exercise demonstrates deep algorithmic competence in handling complex probabilistic structures. Gain immediate access to the full problem statement and professional solution through our paid subscription plan.
Coding & Leetcode-style QuestionsgraphsamplingrandomizationHit Counter with Rolling-Window QPS
3/5Design and implement a high-performance data structure for Databricks that tracks event frequencies over sliding temporal periods. The challenge asks you to record timestamped occurrences and efficiently calculate throughput metrics across dynamic time intervals under high-concurrency constraints. It tests your knowledge of time-window algorithms and memory management. Access to the full problem statement, complexity analysis, and efficient code solution requires a subscription.
Coding & Leetcode-style Questionssliding-windowin-memoryrate-limitingDesign a Network Throttling / Rate-Limiting System
4/5Inspired by real-world distributed systems challenges at Databricks, this system architecture task requires designing a robust traffic throttling and rate-limiting framework for both ingress and egress channels. You will explore multi-tenant traffic management, protective degradation strategies, and mechanisms to prevent cascading backend failures under heavy load. Read the exhaustive architectural guide and expert commentary by subscribing today.
System Design for MLrate-limitingthrottlingbackpressureML System to Detect Harmful LLM Content
4/5This Databricks machine learning architecture exercise challenges candidates to design a robust pipeline for intercepting and filtering objectionable text generated by large language models. The problem explores dataset curation, handling severe class imbalance, multi-modal classification trade-offs, and continuous monitoring against adversarial model drift. Furthermore, it addresses policy governance, human-in-the-loop oversight, and automated threshold tuning. To explore the detailed system blueprint and comprehensive architectural solution, a paid subscription is necessary.
System Design for MLcontent-moderationai-safetyevaluationPath Between Nodes in a Fibonacci Tree
4/5Reported as a challenging Databricks interview question, this task involves navigating massive recursively defined binary trees without actually instantiating the nodes in memory. You must rely on mathematical properties and preorder traversal formulas to locate the lowest common ancestor and trace the exact route between two given nodes. This problem tests advanced recursive comprehension, mathematical deduction, and tree traversal optimization. Unlock the complete problem statement, algorithmic breakdown, and production-ready solution by subscribing.
Coding & Leetcode-style Questionstreerecursionlca
Companies that ask similar questions
Databricks interview FAQ
- How many Databricks interview questions are available?
- 34 reported Databricks questions, the largest group being Coding & Leetcode-style Questions (23).
- How hard is the Databricks interview?
- Across the questions we track, Databricks averages 3.5 out of 5: 3 at 2/5, 13 at 3/5, 17 at 4/5, 1 at 5/5.
- What topics does Databricks ask about?
- Most often idempotency, dp, object-design, concurrency, grid.