Operational tables with a reliable update timestamp.
Azure SQLPROJECT WALKTHROUGH / ETL / ELT
Azure ETL Pipeline
Orchestrate operational extraction, validation, and cloud warehouse loading with a parameterized pipeline design.
Parameterized copy and validation workflow.
Azure Data FactoryDate-partitioned files with pipeline run metadata.
Azure StorageType casting, standardization, and reconciliation.
SQL · PythonValidated tables for downstream reporting.
SnowflakeUnderstand the system before building it.
This project walks through an orchestration-first design using Azure Data Factory concepts and a cloud SQL source. It covers linked services, datasets, triggers, monitoring, and a Snowflake target as a learning scenario.
Business problem
Make the data need understandable before choosing tools or designing pipelines.
A generic financial operations team needs a consistent daily dataset from operational records for downstream reconciliation and reporting.
Data engineering provides a repeatable way to move, validate, transform, and make data available with clear ownership and operational expectations.
A repeatable design makes the data flow, run outcome, and failure location easier to reason about. No actual banking data or production integration is provided.
Requirements
Separate what the workflow must do from the reliability and operational qualities it needs.
- Extract account and transaction data on a defined schedule
- Load a typed, queryable warehouse target
- Support date-range replay and source reconciliation
- Use configuration rather than hard-coded environment-specific values.
- Add validation, structured run logging, and clear failure boundaries.
- Protect credentials and grant only the access each workload needs.
- Measure freshness, duration, volume, and quality outcomes.
Architecture
A layered view of how data moves from source systems to a useful consumer-facing output.
Operational tables with a reliable update timestamp.
Azure SQLParameterized copy and validation workflow.
Azure Data FactoryDate-partitioned files with pipeline run metadata.
Azure StorageType casting, standardization, and reconciliation.
SQL · PythonValidated tables for downstream reporting.
SnowflakeSource systems
Map each source to its data shape, arrival pattern, ingestion choice, and likely failure modes.
Operational Azure SQL
Account and transaction records
Daily schedule with incremental watermark
ADF copy activity via linked service and parameterized dataset
Implementation flow
Build the pipeline in observable stages so each boundary can be tested and recovered independently.
Data ingestion
- Define linked services for source, landing, and target connections.
- Parameterize processing date and source table.
- Schedule through a trigger and pass explicit run parameters.
- Check file or load completion before transformation begins.
Transformation
- Standardize transaction timestamp and amount types.
- Apply business rules for valid account and transaction state.
- Deduplicate using transaction key and update sequence.
- Record rejected values with a reason rather than hiding them.
-- Illustrative quality check
SELECT business_key, COUNT(*) AS row_count
FROM staged_records
GROUP BY business_key
HAVING COUNT(*) > 1;Storage / warehouse
- Use a landing container for source-aligned snapshots or deltas.
- Keep staging structures separate from curated warehouse tables.
- Publish a reconciliation-ready transaction fact and account dimension.
- Retain run identifiers for traceability.
Data quality
Make quality expectations explicit and decide what happens when a record or batch does not pass.
- Validate required account and transaction identifiers.
- Compare source, landed, and target row counts.
- Check amount range, currency code, and accepted statuses.
- Track data freshness against the planned schedule.
Operations, performance, security & monitoring
A realistic project also explains how the system behaves when inputs change, work slows down, or something fails.
09 / Error handling
- Use activity-level retry only for transient failures.
- Capture the failed activity and pipeline run ID.
- Keep the last successful watermark unchanged until target commit.
- Make replay parameters explicit for safe recovery.
10 / Performance
- Use incremental extraction for large operational tables.
- Tune copy parallelism based on source capacity and measured load.
- Push suitable filtering to the source query.
- Avoid over-parallelizing a constrained SQL source.
11 / Security
- Use managed identity where supported for Azure resources.
- Store external credentials in a secret manager in a real deployment.
- Limit access by pipeline role and environment.
- Mask sensitive account fields in consumer-facing datasets.
Monitoring and observability
Monitor system health and data health together: pipeline status alone does not tell you whether the delivered data is fresh and complete.
- Inspect pipeline and activity run status, duration, and retries.
- Compare rows read, written, and rejected.
- Track freshness and late-file events.
- Alerts and integrations are design concepts only in this walkthrough.
Azure ETL Pipeline monitoring signals shown as a design concept. No live pipeline or alert integration is connected.
Deployment flow
Treat infrastructure, SQL, configuration, and validation as reviewed changes that move through separate environments.
Deployment workflow is a learning design. No CI/CD pipeline is implemented by this walkthrough.
Challenges and solutions
Strong project explanations show the problem-solving process, not only the happy path.
The source system has a limited query window.
Use bounded incremental extraction and coordinate parallelism with the source owner.
A scheduled run starts before the source export is complete.
Add a file/data readiness gate and a bounded wait/retry design.
A pipeline retry would reload already-written rows.
Use idempotent target keys or partition replacement and only advance the checkpoint after a successful commit.
How to explain this project in an interview
Use this outline to structure a truthful explanation. Adapt it to work you personally completed; this sample is not a claim about your experience.
EXAMPLE INTERVIEW EXPLANATIONExample interview explanation: “The learning design extracts account and transaction changes from Azure SQL through a parameterized ADF pipeline. Linked services define connections, datasets describe locations and structure, and a scheduled trigger supplies a processing window. Data lands with a run ID, then validation and transformations prepare warehouse tables. I would compare source and target counts, preserve the previous watermark on failure, and monitor activity duration, retries, and freshness. The credentials, alerting, and deployment details would be environment-specific in a real implementation.”
Practice the follow-up.
What is the difference between a linked service and a dataset?
How do you parameterize a reusable pipeline?
How would you prevent a watermark advancing after a failed load?
Which monitoring signals would you check after a run?
Work through the build.
Tick items as you explore. This checklist is session-only and is not saved.