Round 1 – Technical Screening

Format: 90-minute online assessment

DSA Questions

🔹 Array-based Question

🔹 Required efficient manipulation and traversal techniques.

🔹 Focused on optimal time and space complexity.

Matrix-based Question (BFS)

🔹 Problem involving Breadth-First Search (BFS) on a matrix.

🔹 Tested understanding of graph traversal techniques and edge case handling.

SQL Question

A complex SQL problem involving:

🔹 Multiple CTEs (Common Table Expressions)

🔹 Sequential transformation of data

🔹 Final output through joins and aggregations

Round 2 – SQL Deep Dive

Introduction

🔹 General background discussion and overview of previous roles.

SQL Scenarios

Rolling Mean per Product

🔹 Given a product table with dates, implement a rolling mean over 3 consecutive dates.

🔹 Used window functions with UNBOUNDED PRECEDING.

CTE + Join + RANK()

🔹 Two tables provided.

🔹 Required: A CTE, Join operation, RANK() window function

🔹 Follow-up: Modify solution to use a LEFT JOIN for inclusive results.

SQL Concepts Discussion

Indexing Types:

🔹 Clustered vs Non-clustered

🔹 Bitmap, B-Tree, etc.

Partitioning:

🔹 Horizontal vs Vertical

🔹 Partition pruning techniques

File Formats:

🔹 CSV, Parquet, ORC

🔹 When to use which based on performance and use case

Round 3 – Data Governance and Practices

Introduction

🔹 Discussion around prior work experience and roles.

Behavioral & Conceptual Topics

Expedia Value – “Force Simplicity”

Asked for a significant real-life instance where I:

🔹 Reduced complexity

🔹 Created clear, impactful outcomes

User-Centricity

🔹 Building with user empathy

🔹 Gathering feedback and improving data products

Data Governance

🔹 Access control

🔹 Data lineage

🔹 Auditability

🔹 Metadata management

Data Cleaning & BI Practices

🔹 End-to-end cleaning pipelines before BI integration

🔹 Dealing with nulls, duplicates, inconsistent formats

Challenges & Learnings

Past challenges related to:

🔹 Pipeline maintenance

🔹 Stakeholder alignment

🔹 Data quality