Oracle Online Assessment 2026: OA Pattern + Solutions

Quick answer (updated 8 June 2026): Oracle's fresher and new-grad software Online Assessment in 2026 typically blends coding with aptitude and computer-science-fundamentals sections (DBMS, OS, OOP), reflecting Oracle's database and enterprise-software focus. The coding portion features one to three DSA problems, auto-graded with partial scoring. The pattern below is compiled from 2023 to 2025 candidate reports, not an official spec, so confirm the sections and timing in your invite from the Oracle careers portal. Given Oracle's domain, expect more SQL and DBMS weight than at a pure-product company.

Oracle's OA is broader than a coding test, especially on database fundamentals. Candidates who drill only DSA and skip SQL and DBMS underperform. This guide breaks down the pattern, the repeating topics, and worked solutions.

Oracle OA Structure for Freshers

Based on candidate reports for 2023 to 2025 fresher and new-grad batches:

Sections and timing are candidate-reported (2023 to 2025) and vary by role and drive. Database and -DBA-track roles weight SQL and DBMS more. Your invite email is binding.

Topics That Repeat in the Oracle OA

Compiled from candidate reports across 2023 to 2025; relative frequency, not an official syllabus:

Relative frequencies from candidate aggregates (2023 to 2025), labelled approximate. Oracle weights DBMS and SQL more than typical product OAs.

Worked Solution 1: Arrays

Problem: Given an array, move all zeros to the end while keeping the order of non-zero elements, in place.

Approach: Two pointers. One scans; the other marks the next slot for a non-zero value. After placing all non-zeros, fill the rest with zeros.

def move_zeros(nums):
    slot = 0
    for x in nums:
        if x != 0:
            nums[slot] = x
            slot += 1
    for i in range(slot, len(nums)):
        nums[i] = 0
    return nums

Complexity: O(n) time, O(1) space. The in-place, order-preserving constraint is the point; a sort would break the ordering.

Worked Solution 2: Hashing

Problem: Given two arrays, return their intersection (distinct common elements).

Approach: Put one array in a set, then collect elements of the other that are present, deduplicating with a result set.

def intersection(a, b):
    set_a = set(a)
    return list({x for x in b if x in set_a})

Complexity: O(n + m) time, O(n) space. The follow-up "what if both arrays are sorted and huge?" leads to a two-pointer merge with O(1) extra space.

Worked Solution 3: Strings

Problem: Given a string, find the first non-repeating character and return its index, or -1 if none.

Approach: Count character frequencies in one pass, then scan again for the first character with a count of one.

from collections import Counter

def first_unique_char(s):
    counts = Counter(s)
    for i, ch in enumerate(s):
        if counts[ch] == 1:
            return i
    return -1

Complexity: O(n) time, O(1) space (bounded alphabet). Two passes keep it linear and clean.

SQL and DBMS Section

Oracle's domain means the DBMS and SQL sections carry real weight. Be ready to:

• Write joins: inner, left, right, and self joins on sample schemas.
• Use aggregation: GROUP BY, HAVING, COUNT, SUM, AVG.
• Explain normalisation: 1NF through 3NF, and why you would normalise or denormalise.
• Reason about indexing: when an index helps and its cost on writes.
• Understand transactions: ACID properties, isolation levels, deadlock.

A sample SQL task: "Find the second-highest salary from an Employees table." A clean answer uses a subquery or a window function (DENSE_RANK). Practise writing such queries by hand, since the OA may not give you autocomplete.

Oracle OA Timing Strategy

1. Budget time per section. Coding, aptitude, and CS fundamentals each need attention; do not sink all your time in coding.
2. Use partial scoring in coding. Submit a working solution, then optimise.
3. Do not skip SQL prep. For Oracle, DBMS and SQL can be decisive.
4. Move fast on aptitude. Mark-and-move; do not over-invest in one question.
5. Handle edge cases in coding. Empty input, single element, duplicates.

How to Prepare for the Oracle OA

• Drill arrays, strings, hashing, trees, and recursion for the coding section.
• Revise DBMS deeply: normalisation, joins, indexing, transactions, and write SQL queries by hand.
• Brush up OS fundamentals: processes, threads, deadlock, scheduling.
• Practise aptitude (quant and logical) under time pressure.

See Oracle interview questions 2026 and Oracle off campus drive 2026 for the wider path.

Eligibility and Key Dates (Reference)

Oracle hires freshers through campus drives, off-campus openings, and graduate and intern programs across software, cloud, and database tracks. The reference criteria below are compiled from candidate reports for 2023 to 2025 cycles and vary by role; the binding eligibility is whatever the specific job notification on the Oracle careers portal states.

Eligibility figures are candidate-reported references (2023 to 2025), not official cutoffs. Oracle posts roles through the year; watch its careers portal and verified channels for live drives and their exact eligibility windows and dates. The job notification is binding.

More Worked SQL and Coding Problems

Worked SQL 1: Nth-Highest Salary

A frequent Oracle DBMS question, generalising the second-highest case.

SELECT salary
FROM (
    SELECT salary, DENSE_RANK() OVER (ORDER BY salary DESC) AS rnk
    FROM Employees
) ranked
WHERE rnk = :n;

Be ready to explain DENSE_RANK versus RANK and how ties are handled, a common Oracle follow-up.

Worked SQL 2: Department-wise Highest Earner

Use a window function partitioned by department.

SELECT name, dept_id, salary
FROM (
    SELECT name, dept_id, salary,
           RANK() OVER (PARTITION BY dept_id ORDER BY salary DESC) AS rnk
    FROM Employees
) t
WHERE rnk = 1;

This tests partitioned window functions, which Oracle's domain makes likely.

Worked Coding: Group Anagrams (Hashing)

Bucket words by a sorted-character signature.

from collections import defaultdict

def group_anagrams(words):
    groups = defaultdict(list)
    for w in words:
        groups[''.join(sorted(w))].append(w)
    return list(groups.values())

Time O(n times k log k).

Worked Coding: Climbing Stairs (DP)

Count ways to climb n stairs by 1 or 2 steps.

def climb(n):
    a, b = 1, 1
    for _ in range(n):
        a, b = b, a + b
    return a

Time O(n), space O(1).

Managing the Breadth of the Oracle OA

The Oracle OA is broader than most company assessments, and the candidates who clear it are often those who manage its breadth well rather than those who are strongest in any single area. A typical assessment spans coding, aptitude, and computer-science fundamentals, with SQL and DBMS prominent for many roles, so a candidate who spends all their time on coding and neglects the rest leaves easy marks on the table. Treating the OA as a multi-section test with a time budget for each part is the right mental model.

In practice this means deciding in advance roughly how long you will spend on each section and sticking to it. For the coding section, apply the usual discipline: read constraints to infer complexity, exploit partial scoring, and handle edge cases. For aptitude, move quickly, mark and move, and do not let one hard question consume time the other sections need. For the CS-fundamentals and SQL portions, lean on preparation rather than improvisation, since these reward recall of normalisation, indexing, transactions, and query syntax that you either know or do not. The asymmetry is useful: aptitude and fundamentals questions are often faster to answer when prepared than a hard coding problem, so banking those marks efficiently frees time for the coding section.

The overall takeaway is that Oracle rewards well-rounded preparation. A balanced candidate who is solid across coding, aptitude, DBMS, and SQL typically outperforms a coding specialist who is weak elsewhere, precisely because the assessment is designed to test breadth. Build a study plan that gives genuine time to DBMS and SQL alongside DSA, and practise the full multi-section format under a timer so the breadth feels manageable rather than overwhelming on the day.

Why DBMS and SQL Are Decisive at Oracle

Oracle's identity as a database and enterprise-software company shapes its assessment in a way candidates often underestimate: DBMS and SQL frequently carry more weight than at a pure product company, and neglecting them is a common reason otherwise strong coders underperform. Understanding why these areas matter, and what depth is expected, lets you prepare for Oracle's actual bar rather than a generic coding bar.

On the SQL side, be ready to write queries by hand, since the assessment may not give you autocomplete. The bread-and-butter skills are joins (inner, left, right, and self joins on sample schemas), aggregation with GROUP BY and HAVING, and subqueries. Beyond those, window functions like RANK, DENSE_RANK, and ROW_NUMBER come up for problems like the Nth-highest salary or the top earner per department, and being able to use them, and explain how they differ, signals real depth. Practise writing and dry-running these queries until they are automatic.

On the DBMS-concepts side, expect normalisation (explain 1NF through 3NF with an example, and say when you would denormalise for performance), indexing (how an index speeds reads and what it costs on writes), transactions and the ACID properties, and isolation and concurrency at a conceptual level. These are not abstract; they reflect the kind of reasoning Oracle engineers do daily. The practical preparation is to treat DBMS and SQL as a first-class part of your study plan, equal to DSA, rather than an afterthought, and to write real queries by hand under a timer so the assessment's hand-written format does not slow you down.

Why Candidates Lose Marks in the Oracle OA

Candidate reports point to recurring reasons strong candidates underperform:

• Neglecting SQL and DBMS. For Oracle's domain, weak SQL or normalisation knowledge is a notable gap.
• Sinking all time in coding. The OA spans coding, aptitude, and CS fundamentals; budget time across sections.
• Skipping edge cases. Empty input, single element, and duplicates are common hidden tests.
• Over-investing in aptitude questions. Mark and move; do not let one question eat your time.
• Misreading constraints. Large inputs rule out quadratic solutions.

Preparation Timeline (6 to 8 Weeks)

• Weeks 1 to 2: Foundations. Arrays, strings, hashing, plus DBMS basics and SQL query writing by hand.
• Weeks 3 to 4: Core DSA plus DBMS depth. Trees, recursion, basic DP, normalisation, indexing, and joins.
• Weeks 5 to 6: OS and aptitude. Processes, threads, deadlock, scheduling, and timed aptitude practice.
• Weeks 7 to 8: Mocks. Full timed mock OAs across coding, aptitude, and CS sections, plus hand-written SQL drills.

Related Resources

• Oracle off campus drive 2026, eligibility, timeline, and hiring cycle
• Oracle interview questions 2026, commonly asked questions across rounds
• Oracle placement papers 2026, solved past-drive papers
• Oracle India placement papers 2026, India-specific solved papers
• 7-day coding round crash plan 2026, last-week prep
• Off campus placement guide 2026, the master off-campus guide

FAQs: Oracle Online Assessment 2026

Q: What sections are in the Oracle OA?

Candidate reports for 2023 to 2025 describe a mix of coding (one to three DSA problems), aptitude, and CS-fundamentals MCQs (DBMS, OS, OOP), with SQL for some roles. The exact composition varies by role and drive; your invite email lists the sections.

Q: Does Oracle test SQL in its assessment?

For many roles, yes, given Oracle's database focus. Candidate reports mention SQL query writing and DBMS concepts like joins, normalisation, indexing, and transactions. Practise writing queries by hand.

Q: How hard are Oracle OA coding problems?

Candidate reports place them at mostly medium difficulty. The differentiator is breadth: you must clear coding, aptitude, and CS fundamentals, not just one section. Budget your time across all parts.

Q: What DSA topics should I prioritise for Oracle?

Arrays and strings, hashing, trees, and recursion appear most in candidate reports. Pair these with strong DBMS, SQL, and OS fundamentals for Oracle's domain.

Q: Is there partial scoring in the Oracle OA coding section?

Candidate reports describe auto-graded coding with partial credit on hidden test cases. Submit a working partial solution rather than leaving a problem blank, and aim to pass as many cases as possible.

Q: How should I prepare for the Oracle DBMS section?

Revise normalisation (1NF to 3NF), joins, indexing trade-offs, and transactions and ACID properties, and practise writing SQL queries like "find the second-highest salary" by hand. For Oracle, DBMS depth can be decisive.

Q: Which SQL window functions does Oracle expect?

RANK, DENSE_RANK, and ROW_NUMBER come up for problems like the Nth-highest salary or the top earner per department. Be able to use them and explain how they differ, especially how RANK and DENSE_RANK handle ties, since Oracle's database focus makes these likely.

Q: How do I budget time across the Oracle OA sections?

Allocate time to coding, aptitude, and CS or SQL deliberately rather than sinking it all in coding. The OA spans multiple sections, and for Oracle, DBMS and SQL can be decisive, so do not let them go unattempted because you over-invested in one coding problem.

Q: Is competitive programming enough for the Oracle OA?

No. Strong DSA helps, but Oracle's breadth, aptitude, CS fundamentals, and especially DBMS and SQL, means competitive-programming skill alone is insufficient. Prepare SQL query writing and DBMS concepts as a first-class part of your plan.