Databricks Coding Interview Questions
27 Databricks coding interview problems with full optimal solutions — 18 easy, 7 medium, 2 hard. Every problem ships with multiple approaches (brute-force first, then the optimal), complexity tables for each, company-specific tips on what an Databricks interviewer values, and a FAQ section.
Showing 10 problems of 27
- #4easysometimes asked
4. Remove Duplicates from Sorted Array
Modify a sorted array in-place to remove duplicates and return the new length. Databricks uses this to test the two-pointer / read-write head pattern that shows up in every distributed dedup operator.
- #5easysometimes asked
5. Remove Element
Remove all occurrences of a value from an array in-place. Databricks uses this as the in-place-filter primitive that maps onto Spark's filter operator on a partition.
- #6easysometimes asked
6. Search Insert Position
Given a sorted array, return the index where a target should be inserted to keep it sorted. Databricks uses this to verify you can write a binary search that returns the LEFT bound, which is the canonical primitive for range partitioning.
- #8easyrarely asked
8. Plus One
Given a non-empty array of digits representing a non-negative integer, add one to the integer. Databricks asks this to see if you handle the carry-propagation cleanly and whether you reach for in-place mutation when the structure allows.
- #9easysometimes asked
9. Merge Sorted Array
Merge two sorted arrays into the first one, in-place, where the first has trailing space to hold the result. Databricks uses this to test the back-to-front merge trick, which is the same memory-efficient pattern their sort-merge join uses.
- #10easysometimes asked
10. Binary Tree Inorder Traversal
Return the inorder traversal of a binary tree's nodes' values. Databricks asks this to see if you can write both the recursive and iterative versions and explain why the iterative one matters in JVM-stack-bounded environments.
- #11easyrarely asked
11. Same Tree
Check whether two binary trees are structurally identical with the same values. Databricks uses this to test recursive pattern-matching, which is the same template Catalyst uses to compare query subtrees during optimizer rule application.
- #12easyrarely asked
12. Symmetric Tree
Determine if a binary tree is a mirror of itself around its center. Databricks asks this to test paired recursion — comparing two pointers that walk in opposite directions, which is the same primitive used in plan-folding and palindrome detection.
- #14easysometimes asked
14. Balanced Binary Tree
Determine if a binary tree is height-balanced. Databricks asks this to test the post-order pattern where you return information up the tree to avoid recomputing heights at every node.
- #15easysometimes asked
15. Minimum Depth of Binary Tree
Find the minimum depth of a binary tree (distance from root to nearest LEAF). Databricks asks this because it tests whether you can distinguish 'null child' from 'leaf' — a subtle case that catches candidates who only memorized max-depth.
Related interview-prep guides
CodeSignal GCA for Tech Interviews in 2026: The Complete Guide
The CodeSignal General Coding Assessment is a 70-minute, four-task timed test scored on a 600 to 850 scale, used as a filter by Goldman Sachs, Capital One, Robinhood, Brex, and a growing list of tech and finance employers. This guide breaks down what it tests, how it scores, what it tracks during your session, and how a modern desktop setup pairs with it without showing up in proctored recordings.
System Design Interview Guide for CS New Grads (2026): Framework, Templates, Cheat Sheet
The new-grad system design interview is a vocabulary check, a structure check, and a communication check, not a senior architect evaluation. This guide gives you a 4-step framework, a 12-template cheat sheet, a 45-minute time budget, the five canonical problems that carry 80% of new-grad rotations, and a side-by-side of HLD vs LLD vs machine-learning-system-design. Built for the CS new grad who has solved 600 LeetCode problems but never drawn a load balancer.
How to Cold-Email a CS Recruiter as a New Grad in 2026 (Templates Inside)
Yes, cold-emailing a CS recruiter still works for new grads in 2026, but the playbook has narrowed. Generic templates get flagged as spam by humans and email clients alike. What books a call now is short, specific, and respectful of the recruiter's time: a company-specific opener, one-sentence background, one binary ask, and a three-touchpoint follow-up cadence.