Oracle interview practice
Practice from 35 Oracle-tagged public coding problems, organized only by the stage, topic, difficulty, and recency metadata FastPrep can verify. The broader public catalog also includes 12 system-design exercises, 1 low-level-design exercise.
OA practice path
Build a timed implementation rhythm from prompt to edge cases. Problems are ranked by repeated public catalog sightings.
| Company | Problem | Difficulty | Public evidence | Action |
|---|---|---|---|---|
OROracle | First Balanced Removal Index | Unrated | 1 public reportLast reported Dec 2025 | Practice |
OROracle | Find Circle NumberUnion Find | Medium | 1 public reportLast reported Oct 2024 | Practice |
OROracle | Create Lexicographically Largest PermutationGraphDepth-First Search | Hard | 1 public reportLast reported Sep 2024 | Practice |
OROracle | Array Reduction 1HeapGreedy | Easy | 1 public reportLast reported Feb 2024 | Practice |
OROracle | Balancing ParenthesesStringStack | Easy | 1 public reportLast reported Feb 2024 | Practice |
OROracle | Last and Second-LastString | Easy | 1 public reportLast reported Feb 2024 | Practice |
OROracle | Merge 2 ArraysArrayTwo Pointers | Easy | 1 public reportLast reported Feb 2024 | Practice |
OROracle | Minimum Difference SumSortingGreedy | Easy | 1 public reportLast reported Feb 2024 | Practice |
OROracle | Powers of 2Bit ManipulationMath | Easy | 1 public reportLast reported Feb 2024 | Practice |
OROracle | Adding Two NumbersMath | Easy | 1 public reportLast reported Feb 2024 | Practice |
OROracle | Cardinality SortingSortingBit Manipulation | Easy | 1 public reportLast reported Feb 2024 | Practice |
OROracle | REST API: Discounted PriceDesignMath | Easy | 1 public reportLast reported Feb 2024 | Practice |
Phone practice path
Practice solving while explaining assumptions, tradeoffs, and complexity. Problems are ranked by repeated public catalog sightings.
| Company | Problem | Difficulty | Public evidence | Action |
|---|---|---|---|---|
OROracle | Best Time to Buy and Sell StockArrayDynamic Programming | Easy | 4 public reportsLast reported Aug 2026 | Practice |
OROracle | Time-Based Key-Value StoreHash TableBinary Search | Medium | 3 public reportsLast reported Aug 2026 | Practice |
OROracle | Alphabetically Maximum SubstringStringTwo Pointers | Hard | 2 public reportsLast reported Aug 2026 | Practice |
OROracle | Bottom View of a Binary TreeTreeBreadth-First Search | Medium | 2 public reportsLast reported Aug 2026 | Practice |
OROracle | Top-K URLs Overall and in the Last 24 HoursArrayHash Table | Medium | 1 public reportLast reported Aug 2026 | Practice |
OROracle | Remove Even-Positioned Linked-List NodesLinked List | Easy | 1 public reportLast reported Aug 2026 | Practice |
OROracle | Sort Departments by EnrollmentArrayHash Table | Medium | 1 public reportLast reported Aug 2026 | Practice |
OROracle | Maximum of Window MinimumsArraySliding Window | Medium | 1 public reportLast reported Aug 2026 | Practice |
OROracle | Merge k Sorted ListsLinked ListHeap | Hard | 1 public reportLast reported Jul 2026 | Practice |
OROracle | Implement a Queue Using Two StacksStackQueue | Easy | 1 public reportLast reported Jul 2026 | Practice |
Onsite practice path
Practice complete solutions and defend the choices behind them. Problems are ranked by repeated public catalog sightings.
16 Oracle-tagged Onsite problems available.
| Company | Problem | Difficulty | Public evidence | Action |
|---|---|---|---|---|
OROracle | Best Time to Buy and Sell StockArrayDynamic Programming | Easy | 4 public reportsLast reported Aug 2026 | Practice |
OROracle | Time-Based Key-Value StoreHash TableBinary Search | Medium | 3 public reportsLast reported Aug 2026 | Practice |
OROracle | Add One to a Number Represented as DigitsArrayMath | Easy | 2 public reportsLast reported Aug 2026 | Practice |
OROracle | Top K Frequent Elements with Larger-Value Tie BreakArrayHash Table | Medium | 2 public reportsLast reported Aug 2026 | Practice |
OROracle | Enumerate Right-and-Down Matrix PathsMatrixBacktracking | Medium | 2 public reportsLast reported Aug 2026 | Practice |
OROracle | Maximize Movie Ratings Without Consecutive SkipsArrayDynamic Programming | Medium | 2 public reportsLast reported Aug 2026 | Practice |
OROracle | Bottom View of a Binary TreeTreeBreadth-First Search | Medium | 2 public reportsLast reported Aug 2026 | Practice |
OROracle | Count Dropped Rate-Limited RequestsArraySliding Window | Medium | 2 public reportsLast reported Aug 2026 | Practice |
OROracle | Keep at Most K Occurrences in a Sorted ArrayArrayTwo Pointers | Medium | 2 public reportsLast reported Aug 2026 | Practice |
OROracle | Swap Two Integers Without a Temporary VariableBit ManipulationMath | Easy | 2 public reportsLast reported Aug 2026 | Practice |
OROracle | Accounts MergeArrayHash Table | Medium | 1 public reportLast reported Aug 2026 | Practice |
OROracle | Maximum Height of Every IslandMatrixDepth-First Search | Medium | 1 public reportLast reported Aug 2026 | Practice |
OROracle | Maximum Subarray Sum with Length at Most KArrayPrefix Sum | Hard | 1 public reportLast reported Aug 2026 | Practice |
OROracle | Place K Buildings to Minimize Maximum Grid DistanceMatrixBacktracking | Hard | 1 public reportLast reported Aug 2026 | Practice |
OROracle | Split a String into Three PalindromesStringDynamic Programming | Medium | 1 public reportLast reported Aug 2026 | Practice |
OROracle | Run-Length String CompressionStringTwo Pointers | Easy | 1 public reportLast reported Aug 2026 | Practice |
01 · Preparation plan
Oracle's mixed coding and design catalog supports a storage-oriented study path. First resolve identity across records, then preserve values over time, then reason about a query whose answer changes as events age. This is engineering practice, not an Oracle Database certification syllabus. This is a suggested practice sequence, not the employer's interview process. Your invitation and recruiter guidance remain the source of truth.
Use account merging to distinguish shared identifiers from identical display names. A chain of overlapping records must produce the same grouping regardless of input order.
The time-based store makes historical lookup concrete. Specify which prior version is visible and what a query before the first write should return.
Use the URL-ranking exercise to maintain two different aggregates over the same event stream. Expiration must affect the recent ranking without erasing lifetime evidence.
02 · Broader technical practice
These public Oracle-tagged exercises cover additional technical formats. They are included only when a verified catalog record and a crawlable practice page both exist.
Design a deliberately small URL-shortening core, then evolve it into a highly available service whose fixed logical shards can move safely as physical storage capacity grows.
Open practiceDesign a high-cardinality metrics database for durable ingestion, range queries, rollups, late data, and retention.
Open practiceDesign a regional software load balancer with a chosen L4 or L7 data path, versioned policies, backend health, and graceful draining.
Open practiceModel and implement an in-memory key-value store whose writes commit to active and passive replicas together or fail without changing either.
Open practiceDesign a multi-tenant platform that durably ingests structured application logs and makes recent events searchable with explicit freshness and replay semantics.
Open practiceDesign event ingestion, candidate retrieval, ranking, and serving for a bounded personalized user-item catalog.
Open practiceDesign a multi-tenant distributed limiter that smooths priority and regular traffic under versioned quotas, retries, and partial failure.
Open practiceIngest high-volume service logs and return the top error-producing services in the trailing five minutes.
Open practiceMaintain the top one hundred users by event count over a continuously moving one-hour window.
Open practiceDeliver a scheduled message to between one and ten thousand recipients within one second of its due time.
Open practiceDesign a secure, replayable pipeline that turns millions of healthcare records into trustworthy curated datasets.
Open practiceDesign an on-demand video platform that ingests, publishes, authorizes, and streams adaptive media to viewers at global scale.
Open practiceDesign a service that opens untrusted web pages inside disposable remote browser sessions and streams a safe interactive view to users.
Open practice03 · Evidence boundary
It means practicing transferable implementation, testing, and technical reasoning with public catalog assets FastPrep tags to Oracle. It does not mean FastPrep has access to the company's assessments or any private interview bank.
Repeated public sightings and last-reported dates can help you prioritize practice, but they cannot predict the questions, format, or platform in a specific interview.
04 · Plain answers
This page owns technical-practice intent for Oracle. Hiring activity, timelines, and market signals remain on the separate hiring-insights page.
Not as a complete course. The verified assets support coding and system-design practice. Storage-related exercises are useful for discussing data structures and query tradeoffs, but they do not establish a SQL question bank, DBA role curriculum, or the current requirements of a particular Oracle team.
No. FastPrep is an independent interview-preparation product and is not affiliated with Oracle. The page uses FastPrep's public practice catalog and does not claim official, private, leaked, or proprietary employer questions.
Stage labels come from FastPrep's public problem metadata. A problem can carry more than one reported stage, and hiring processes can change by role, level, location, and date. Treat the labels as preparation context, not a guarantee.
Start with the stage named in your invitation or recruiter message. If no stage is known, use the largest available set to build general problem-solving fluency, then rehearse explanation and testing separately.
No. Public catalog counts, stage tags, and last-reported dates can help prioritize practice, but they cannot predict a specific interview's questions, sequence, timing, or platform.
Your next stage, made concrete
Start with the stage named in your invitation, then use public evidence as context—not as a promise of what you will be asked.
Open the practice set