Ernst & Young Advisory Services Sdn Bhd Software Engineer Interview Guide

The 60-second brief

As a Software Engineer at Ernst & Young Advisory Services Sdn Bhd, you serve as a critical bridge between complex business challenges and scalable technological solutions. You are not merely writing code; you are architecting digital transformations that enable clients to navigate regulatory, tax, and operational complexities in an increasingly digital-first global economy. Your work will directly influence the efficiency of platforms used by major organizations, ranging from indirect tax technology engines to government and public sector infrastructure. You will operate in an environment where technical precision meets strategic consulting. Whether you are building robust microservices, optimizing SQL pipelines, or integrating cloud-based architecture, your impact is measured by the reliability, security, and scalability of the systems you deliver.

This guide is scoped to a Software Engineer candidate at Ernst & Young Advisory Services Sdn Bhd.

Focus areas

• SQL
• C#
• Problem Solving

The Ernst & Young Advisory Services Sdn Bhd interview process

Ernst & Young Advisory Services Sdn Bhd candidates report 4 rounds over 3-5 weeks. The stages below are what candidates describe, not a published process.

Automated Assessments

Candidates complete assessments focusing on logic and coding skills.

What to demonstrate

• Candidates complete assessments focusing on logic and coding skills
• Depth in SQL

How to prepare

• Answer aloud and timed: Explain the core concepts of OOPs and how you implement them in C# or Java.
• Answer aloud and timed: How do you flatten an array without using built-in methods?

Technical Interviews

Multiple rounds of interviews assessing technical knowledge and problem-solving abilities.

What to demonstrate

• Multiple rounds of interviews assessing technical knowledge and problem-solving abilities
• Depth in SQL

How to prepare

• Answer aloud and timed: Can you explain the difference between bind, call, and apply in JavaScript?
• Answer aloud and timed: What are the primary differences between Entity Framework Core and traditional ADO.NET?

Behavioral Interviews

Interviews that evaluate candidates' soft skills and cultural fit within the company.

What to demonstrate

• Interviews that evaluate candidates' soft skills and cultural fit within the company
• Depth in SQL

How to prepare

• Prepare three examples from your own work, each with a decision you made and an outcome you can quantify.
• Re-read the description of the behavioral interviews above and write down what you would ask to confirm before it.

Final Technical Evaluation

A comprehensive assessment to finalize the candidate's technical capabilities.

What to demonstrate

• A comprehensive assessment to finalize the candidate's technical capabilities
• Depth in SQL

How to prepare

• Answer aloud and timed: How do you handle data consistency across distributed systems?
• Answer aloud and timed: Explain how you would design an SSIS pipeline for large-scale data migration.

Where candidates lose points

Structure your answers

Use the STAR method (Situation, Task, Action, Result) for all behavioral questions to keep your responses concise and impactful.

Ask insightful questions

At the end of your interview, ask about the team’s current technical challenges or how the department integrates new technologies. This shows genuine interest and strategic thinking.

Know your resume

Be prepared to explain every line on your resume. If you list a technology, ensure you can discuss it with confidence.

Always research the specific team you are interviewing with

If the job posting mentions "Tax Technology," look up how software is currently transforming the tax industry to gain an edge during your interview.

Questions & practice

Explain the core concepts of OOPs and how you implement them in C# or Java.

Medium · Technical Fundamentals and Coding

Approach

1. Restate the input: its shape, its size, and what is guaranteed about it.
2. Name the brute-force solution and its complexity before improving on it.
3. Choose the data structure from the access pattern, not from familiarity.
4. State the target complexity and say which constraint rules the naive version out.

Follow-up

• How does this change if the input no longer fits in memory?
• What is the worst case, and how likely is it on real data?

How do you flatten an array without using built-in methods?

Medium · Technical Fundamentals and Coding

Approach

1. Restate the input: its shape, its size, and what is guaranteed about it.
2. Name the brute-force solution and its complexity before improving on it.
3. Choose the data structure from the access pattern, not from familiarity.
4. State the target complexity and say which constraint rules the naive version out.

Follow-up

• How does this change if the input no longer fits in memory?
• What is the worst case, and how likely is it on real data?

Can you explain the difference between bind, call, and apply in JavaScript?

Medium · Technical Fundamentals and Coding

Approach

1. Restate the input: its shape, its size, and what is guaranteed about it.
2. Name the brute-force solution and its complexity before improving on it.
3. Choose the data structure from the access pattern, not from familiarity.
4. State the target complexity and say which constraint rules the naive version out.

Follow-up

• How does this change if the input no longer fits in memory?
• What is the worst case, and how likely is it on real data?

What are the primary differences between Entity Framework Core and traditional ADO.NET?

Medium · Technical Fundamentals and Coding

Approach

1. Restate the input: its shape, its size, and what is guaranteed about it.
2. Name the brute-force solution and its complexity before improving on it.
3. Choose the data structure from the access pattern, not from familiarity.
4. State the target complexity and say which constraint rules the naive version out.

Follow-up

• How does this change if the input no longer fits in memory?
• What is the worst case, and how likely is it on real data?

Describe your approach to optimizing SQL queries and managing database triggers.

Medium · Technical Fundamentals and Coding

Approach

1. Name the grain you start from and join outward from it.
2. Check whether any join is one-to-many before aggregating, or the sums inflate.
3. Say which index the query would use, and what makes it unusable.
4. Handle the rows that do not match: that is usually the actual question.

Follow-up

• How does the query change if that join becomes one-to-many?
• What happens to this when the table is ten times larger?

Find version gaps and relay lag with window functions

Medium · window functions · event tables · frame semantics

outbox_event holds event_id, aggregate_type, aggregate_id, aggregate_version, event_type, payload, status ('pending','published','dead'), attempts, created_at, published_at. A projection is missing rows and you must decide whether the relay skipped events or the consumer dropped them. Write three queries over the last seven days: one listing every aggregate_id whose published aggregate_version sequence has a hole, one giving per-day counts with a running total, and one returning the newest published event per aggregate. For each, say where the window function is evaluated relative to WHERE and LIMIT. PostgreSQL 16.

Approach

1. Gaps: compute lead(aggregate_version) OVER (PARTITION BY aggregate_id ORDER BY aggregate_version) in a subquery, then filter next_version <> aggregate_version + 1 in the outer query. Window functions are evaluated after WHERE, GROUP BY and HAVING and before the outer ORDER BY and LIMIT, so the predicate cannot sit in the same WHERE clause and PostgreSQL 16 has no QUALIFY.
2. Say what the seven-day filter does to the answer: it truncates every partition, so the first row per aggregate has no predecessor inside the window and a hole spanning the boundary is invisible. Widen the window, or join to resource.version as the authority for the true maximum.
3. Running total: SELECT date_trunc('day', created_at) AS d, count() AS n, sum(count()) OVER (ORDER BY date_trunc('day', created_at) ROWS UNBOUNDED PRECEDING). An aggregate inside a window call is legal because grouping runs before windowing. The grouping key is unique per row here so ROWS and RANGE agree, but write the frame anyway — over ungrouped rows with tied timestamps the default RANGE frame pulls in every peer row and the total jumps.
4. Newest per aggregate: DISTINCT ON (aggregate_id) ... ORDER BY aggregate_id, aggregate_version DESC is the cheap PostgreSQL-only form when an index matches that order; row_number() OVER (PARTITION BY aggregate_id ORDER BY aggregate_version DESC) = 1 is the portable form and needs a subquery for the same evaluation-order reason as the gap query.

Follow-up

• Relay failover redelivers events. Does a duplicate break the gap query, and how would you detect one from this table alone?
• Turn the gap check into a continuous monitor rather than a query someone runs after an incident. What does it watch?

Describe the architecture of a Microservices project you have worked on.

Medium · System Design and Architecture

Approach

1. Fix the scope first: who calls this, how often, and what they do when it fails.
2. Name the read and write paths separately; they rarely have the same bottleneck.
3. Choose a partition key and say what query it makes expensive.
4. State the consistency you need, and where you are willing to be stale.

Follow-up

• What breaks first when traffic grows ten times?
• How does this behave when that dependency is down for an hour?

Explain how you would design an SSIS pipeline for large-scale data migration.

Medium · System Design and Architecture

Approach

1. Fix the scope first: who calls this, how often, and what they do when it fails.
2. Name the read and write paths separately; they rarely have the same bottleneck.
3. Choose a partition key and say what query it makes expensive.
4. State the consistency you need, and where you are willing to be stale.

Follow-up

• What breaks first when traffic grows ten times?
• How does this behave when that dependency is down for an hour?

What are the trade-offs when choosing between a relational database and a NoSQL solution?

Medium · System Design and Architecture

Approach

1. Fix the scope first: who calls this, how often, and what they do when it fails.
2. Name the read and write paths separately; they rarely have the same bottleneck.
3. Choose a partition key and say what query it makes expensive.
4. State the consistency you need, and where you are willing to be stale.

Follow-up

• What breaks first when traffic grows ten times?
• How does this behave when that dependency is down for an hour?

Listing latency scales with page size, not with filters

Easy · n+1 · latency · query batching

The tenant listing endpoint reads resource filtered by tenant_id and status, ordered by updated_at DESC, and returns each row plus the owner's display name from app_user and the actor of that resource's latest resource_revision. p99 is 55 ms at 10 rows per page and 1.4 s at 200. Database telemetry shows 401 statements per request, each under 1 ms, and nothing in the slow-query log. Diagnose the cause and give the fix, stating the statement count per request and the p99 you expect afterwards.

Approach

1. Read the counters before forming a theory. 401 statements for 200 rows is one driver query plus two per row, and sub-millisecond execution with an empty slow-query log rules out a bad plan. The time is round trips, which is why it is invisible in every per-query metric and scales with rows returned rather than with filter selectivity.
2. Name the two per-row statements from their normalised text: a single-row app_user lookup by user_id, and a resource_revision lookup by resource_id ordered by version DESC LIMIT 1. Confirm by dropping those two response fields and watching the statement count fall to one. That locates the calls in the serialisation layer, not the repository.
3. Check that the arithmetic accounts for the whole gap. Measure one round trip to the replica in isolation; 400 trips at roughly 3 ms of network plus 0.2 ms of execution is about 1.3 s on top of a 55 ms baseline, which matches. If the multiplication had fallen short, the N+1 would only be part of the story and you would keep looking.
4. Batch both lookups. Collect owner_user_ids and resource_ids from the driver query, then issue WHERE tenant_id = $1 AND user_id = ANY($2) for the users, and PostgreSQL's SELECT DISTINCT ON (resource_id) ... WHERE resource_id = ANY($2) ORDER BY resource_id, version DESC for the latest revision, which the UNIQUE (resource_id, version) index serves directly. On an engine without DISTINCT ON, use a lateral join or a row_number window. Three statements per request at any page size.

Follow-up

• The page size is capped at 200 today. What breaks first if it is raised to 2,000, and is it still this bug?
• How do you stop the next N+1 from reaching production, given that no individual query is slow and the endpoint's tests pass?

Suggested practice checklist

Built from the rounds and topics Ernst & Young Advisory Services Sdn Bhd candidates report.

Day 1 — Map the Ernst & Young Advisory Services Sdn Bhd loop

• Write out the reported sequence: Automated Assessments, Technical Interviews, Behavioral Interviews, Final Technical Evaluation.
• For each round, write one sentence on what it is judging, from the description above, and mark the one you are least ready for.

Deliverable: A one-page map of the 4 reported rounds, with the weakest marked.

Day 2 — Work SQL

• Spend the session on SQL, which Ernst & Young Advisory Services Sdn Bhd candidates report being tested on.
• Write one worked example in SQL and time yourself on it.

Deliverable: One timed worked example in SQL.

Day 3 — Work C#

• Spend the session on C#, which Ernst & Young Advisory Services Sdn Bhd candidates report being tested on.
• Write one worked example in C# and time yourself on it.

Deliverable: One timed worked example in C#.

Day 4 — Work Problem Solving

• Spend the session on Problem Solving, which Ernst & Young Advisory Services Sdn Bhd candidates report being tested on.
• Write one worked example in Problem Solving and time yourself on it.

Deliverable: One timed worked example in Problem Solving.

Day 5 — Answer out loud: Technical Fundamentals and Coding

• Answer aloud, timed: Explain the core concepts of OOPs and how you implement them in C# or Java.
• Answer aloud, timed: How do you flatten an array without using built-in methods?

Deliverable: Spoken answers to 2 reported Technical Fundamentals and Coding question(s), under time.

Day 6 — Answer out loud: System Design and Architecture

• Answer aloud, timed: Describe the architecture of a Microservices project you have worked on.
• Answer aloud, timed: How do you handle data consistency across distributed systems?

Deliverable: Spoken answers to 2 reported System Design and Architecture question(s), under time.

Day 7 — Answer out loud: Behavioral and Situational

• Answer aloud, timed: Why are you interested in Ernst & Young Advisory Services Sdn Bhd specifically, and what do you bring to tech consulting?
• Answer aloud, timed: Tell me about a time you had to balance learning new technologies with your project deliverables.

Deliverable: Spoken answers to 2 reported Behavioral and Situational question(s), under time.

Behavioural preparation

Behavioural rounds judge the decision you made and what it cost.

How do you handle data consistency across distributed systems?

Medium · System Design and Architecture

Approach

1. Pick a story where you made the decision, not one where you watched it.
2. State the situation in two sentences and spend the rest on the reasoning.
3. Give the blast radius: what could have broken, and what you measured.
4. Name the disagreement and how you resolved it with evidence.

Follow-up

• What would you do differently if you ran that again?
• How did you know your change caused the improvement?

Why are you interested in Ernst & Young Advisory Services Sdn Bhd specifically, and what do you bring to tech

Medium · Behavioral and Situational

Why are you interested in Ernst & Young Advisory Services Sdn Bhd specifically, and what do you bring to tech consulting?

Approach

1. Pick a story where you made the decision, not one where you watched it.
2. State the situation in two sentences and spend the rest on the reasoning.
3. Give the blast radius: what could have broken, and what you measured.
4. Name the disagreement and how you resolved it with evidence.

Follow-up

• What would you do differently if you ran that again?
• How did you know your change caused the improvement?

Tell me about a time you had to balance learning new technologies with your project deliverables.

Medium · Behavioral and Situational

Approach

1. Pick a story where you made the decision, not one where you watched it.
2. State the situation in two sentences and spend the rest on the reasoning.
3. Give the blast radius: what could have broken, and what you measured.
4. Name the disagreement and how you resolved it with evidence.

Follow-up

• What would you do differently if you ran that again?
• How did you know your change caused the improvement?

How do you handle situations where project requirements change unexpectedly?

Medium · Behavioral and Situational

Approach

1. Pick a story where you made the decision, not one where you watched it.
2. State the situation in two sentences and spend the rest on the reasoning.
3. Give the blast radius: what could have broken, and what you measured.
4. Name the disagreement and how you resolved it with evidence.

Follow-up

• What would you do differently if you ran that again?
• How did you know your change caused the improvement?

Describe your process for communicating technical blockers to non-technical stakeholders.

Medium · Behavioral and Situational

Approach

1. Pick a story where you made the decision, not one where you watched it.
2. State the situation in two sentences and spend the rest on the reasoning.
3. Give the blast radius: what could have broken, and what you measured.
4. Name the disagreement and how you resolved it with evidence.

Follow-up

• What would you do differently if you ran that again?
• How did you know your change caused the improvement?