Data Engineering & Analytics Infrastructure Topics
Data pipeline design, ETL/ELT processes, streaming architectures, data warehousing infrastructure, analytics platform design, and real-time data processing. Covers event-driven systems, batch and streaming trade-offs, data quality and governance at scale, schema design for analytics, and infrastructure for big data processing. Distinct from Data Science & Analytics (which focuses on statistical analysis and insights) and from Cloud & Infrastructure (platform-focused rather than data-flow focused).
Geospatial and Real Time Processing
Covers design and operation of systems that handle spatial data and low latency event streams. Candidates should explain spatial indexing and query techniques, map matching and coordinate reference considerations, spatial accuracy and privacy trade offs, and storage approaches for geospatial data. For real time processing describe ingestion, messaging patterns, stream processing concepts such as windowing and stateful processing, ordering and delivery semantics, partitioning and scaling strategies, backpressure and fault handling, and trade offs between real time and batch analytics for customer facing metrics.
Business Intelligence and Data Warehouse Architecture
Design end to end business intelligence systems and the underlying data warehouse architecture. Topics include data ingestion patterns for batch and streaming sources, change data capture, transformation layers and the choice between extract transform load and extract load transform approaches, dimensional modeling and schema choices such as star and snowflake schemas, fact and dimension table design, slowly changing dimensions strategies, medallion and layered architectures, and the visualization and consumption layer. Also cover pipeline orchestration, monitoring, observability, data quality checks, and trade offs between centralized and federated approaches as well as real time versus batch processing.
Batch and Stream Processing
Covers design and implementation of data processing using batch, stream, or hybrid approaches. Candidates should be able to explain when to choose batch versus streaming based on latency, throughput, cost, data volume, and business requirements, and compare architectural patterns such as lambda and kappa. Core stream concepts include event time versus processing time, windowing strategies such as tumbling sliding and session windows, watermarks and late arrivals, event ordering and out of order data handling, stateful versus stateless processing, state management and checkpointing, and delivery semantics including exactly once and at least once. Also includes knowledge of streaming and batch engines and runtimes, connector patterns for sources and sinks, partitioning and scaling strategies, backpressure and flow control, idempotency and deduplication techniques, testing and replayability, monitoring and alerting, and integration with storage layers such as data lakes and data warehouses. Interview focus is on reasoning about correctness latency cost and operational complexity and on concrete architecture and tooling choices.
Data Pipeline Scalability and Performance
Design data pipelines that meet throughput and latency targets at large scale. Topics include capacity planning, partitioning and sharding strategies, parallelism and concurrency, batching and windowing trade offs, network and I O bottlenecks, replication and load balancing, resource isolation, autoscaling patterns, and techniques for maintaining performance as data volume grows by orders of magnitude. Include approaches for benchmarking, backpressure management, cost versus performance trade offs, and strategies to avoid hot spots.
SQL-Based Data Validation and Anomaly Detection
Techniques for validating data quality and detecting anomalies using SQL: identifying nulls and missing values, finding duplicates and orphan records, range checks, sanity checks across aggregates, distribution checks, outlier detection heuristics, reconciliation queries across systems, and building SQL based alerts and integrity checks. Includes strategies for writing repeatable validation queries, comparing row counts and sums across pipelines, and documenting assumptions for investigative analysis.
Analytics Platforms and Dashboards
Comprehensive knowledge of analytics platforms, implementation of tracking, reporting infrastructure, and dashboard design to support marketing, product, and content decisions. Candidates should be able to describe tool selection and configuration for platforms such as Google Analytics Four, Adobe Analytics, Mixpanel, Amplitude, Tableau, and Looker, including the trade offs between vendor solutions, native platform analytics, and custom instrumentation. Core implementation topics include defining measurement plans and event schemas, event instrumentation across web and mobile, tagging strategy and data layer design, Urchin Tracking Module parameter handling and cross domain attribution, conversion measurement, and attribution model design. Analysis and reporting topics include funnel analysis, cohort analysis, retention and segmentation, key performance indicator definition, scheduled reporting and automated reporting pipelines, alerting for data anomalies, and translating raw metrics into stakeholder ready dashboards and narrative visualizations. Integration and governance topics include data quality checks and validation, data governance and ownership, exporting and integrating analytics with data warehouses and business intelligence pipelines, and monitoring instrumentation coverage and regression. The scope also covers channel specific analytics such as search engine optimization tools, social media native analytics, and email marketing metrics including delivery rates, open rates, and click through rates. For junior candidates, demonstration of fluency with one or two tools and basic measurement concepts is sufficient; for senior candidates, expect discussion of architecture, pipeline automation, governance, cross functional collaboration, and how analytics drive experiments and business decisions.
Data Lake and Warehouse Architecture
Designing scalable data platforms for analytical and reporting workloads including data lakes, data warehouses, and lakehouse architectures. Key topics include storage formats and layout including columnar file formats such as Parquet and table formats such as Iceberg and Delta Lake, partitioning and compaction strategies, metadata management and cataloging, schema evolution and transactional guarantees for analytical data, and cost and performance trade offs. Cover ingestion patterns for batch and streaming data including change data capture, data transformation approaches and compute engines for analytical queries, partition pruning and predicate pushdown, query optimization and materialized views, data modeling for analytical workloads, retention and tiering, security and access control, data governance and lineage, and integration with business intelligence and real time analytics. Also discuss operational concerns such as monitoring, vacuuming and compaction jobs, metadata scaling, and strategies for minimizing query latency while controlling storage cost.
Data Quality and Edge Case Handling
Practical skills and best practices for recognizing, preventing, and resolving real world data quality problems and edge cases in queries, analyses, and production data pipelines. Core areas include handling missing and null values, empty and single row result sets, duplicate records and deduplication strategies, outliers and distributional assumptions, data type mismatches and inconsistent formatting, canonicalization and normalization of identifiers and addresses, time zone and daylight saving time handling, null propagation in joins, and guarding against division by zero and other runtime anomalies. It also covers merging partial or inconsistent records from multiple sources, attribution and aggregation edge cases, group by and window function corner cases, performance and correctness trade offs at scale, designing robust queries and pipeline validations, implementing sanity checks and test datasets, and documenting data limitations and assumptions. At senior levels this expands to proactively designing automated data quality checks, monitoring and alerting for anomalies, defining remediation workflows, communicating trade offs to stakeholders, and balancing engineering effort against business risk.
Data Quality and System Integration Challenges
Focuses on data integrity, governance, and the operational issues that arise when data moves between systems. Candidates should be able to identify common data quality problems such as duplicates, missing or inconsistent fields, formatting mismatches, schema drift, and validation gaps. Understand how those issues propagate through integration pipelines and impact reporting, analytics, forecasting, and other downstream processes. Discuss reconciliation strategies, validation rules, data cleansing, deduplication, master data management patterns, monitoring and alerting for data anomalies, and policies for schema evolution and versioning. Also cover practical approaches to prevent and remediate integration induced data errors and how to prioritize data quality work across cross-system business workflows (for example, CRM/billing integrations, HR and compensation data feeds, marketing automation pipelines, or product analytics), not just any single business function.