This curriculum spans the technical, operational, and governance dimensions of enterprise data migrations, comparable in scope to a multi-phase advisory engagement supporting large-scale data lake modernizations across hybrid environments.
Module 1: Assessing Source Systems and Data Landscape
- Identify all operational databases, data warehouses, and legacy flat-file systems requiring inclusion in the migration scope based on business criticality and data lineage.
- Document data ownership, update frequency, and SLAs for each source system to inform migration scheduling and downtime planning.
- Evaluate data encoding formats (e.g., EBCDIC, UTF-16) and character set inconsistencies across sources to prevent corruption during extraction.
- Map dependencies between source systems and downstream reporting or analytical platforms to prioritize migration sequences.
- Conduct performance profiling of source queries to avoid overloading production systems during bulk extraction.
- Negotiate access permissions with data stewards and IT operations, including read-only roles and audit logging requirements.
- Classify data sensitivity levels (PII, PCI, PHI) across sources to enforce compliance controls early in the migration design.
- Assess source system uptime windows and coordinate with business units to schedule extraction during off-peak hours.
Module 2: Designing Migration Architecture and Data Pipelines
- Select between batch, micro-batch, or real-time ingestion patterns based on source system capabilities and target latency requirements.
- Choose appropriate transport mechanisms (e.g., Sqoop, Kafka Connect, custom JDBC/ODBC scripts) based on source database type and network constraints.
- Design staging layer schema in the target data lake to preserve raw source fidelity, including metadata like extraction timestamps and row-level source identifiers.
- Implement retry logic and dead-letter queues in pipeline workflows to handle transient network or authentication failures.
- Define partitioning and bucketing strategies in the target storage layer to optimize query performance and reduce scan costs.
- Integrate pipeline monitoring hooks (e.g., Prometheus exporters, CloudWatch metrics) to track throughput, latency, and error rates.
- Architect idempotent pipeline steps to enable safe reprocessing without data duplication.
- Size cluster resources (CPU, memory, disk I/O) for ETL workers based on historical data volume and projected growth.
Module 3: Schema Mapping and Data Transformation
- Resolve data type mismatches (e.g., Oracle NUMBER to Parquet DECIMAL) while preserving precision and scale.
- Handle surrogate vs. natural key conflicts when merging data from multiple sources with inconsistent key strategies.
- Implement type 2 slowly changing dimension logic for historical tracking in dimensional models during migration.
- Standardize date, currency, and address formats across sources to ensure consistency in the target environment.
- Apply data masking or tokenization rules during transformation for sensitive fields to meet compliance requirements.
- Design transformation logic to handle schema drift, such as new columns or dropped fields, without pipeline failure.
- Validate referential integrity between migrated fact and dimension tables post-transformation.
- Log transformation decisions and exceptions for auditability and reconciliation with business stakeholders.
Module 4: Data Quality and Validation Frameworks
- Define and automate row count reconciliation checks between source and target systems for each migration batch.
- Implement null rate, value distribution, and uniqueness assertions to detect data corruption or truncation.
- Set up field-level checksums (e.g., SHA-256 on concatenated key fields) to verify data integrity end-to-end.
- Develop sampling strategies for manual validation of high-risk or complex transformations.
- Integrate data profiling tools (e.g., Great Expectations, Deequ) into CI/CD pipelines for regression testing.
- Establish thresholds for acceptable variance in aggregated metrics (e.g., sum, count) between source and target.
- Document false positive cases in validation rules to refine thresholds and avoid alert fatigue.
- Coordinate with business analysts to validate semantic accuracy of transformed business metrics.
Module 5: Performance Optimization and Scalability
- Tune Spark executor memory and parallelism settings based on data skew and cluster node specifications.
- Optimize file sizing in cloud storage (e.g., 128MB–1GB Parquet files) to balance query performance and metadata overhead.
- Implement predicate pushdown and column pruning in extraction queries to reduce data movement.
- Use broadcast joins judiciously for small dimension tables to avoid driver memory pressure.
- Monitor shuffle spill to disk and adjust configurations to minimize I/O bottlenecks.
- Precompute and store frequently used aggregations in materialized views to accelerate validation and reporting.
- Partition large tables by time or region to enable efficient incremental processing and archival.
- Conduct load testing with production-scale data volumes to identify pipeline bottlenecks before cutover.
Module 6: Security, Access Control, and Compliance
- Enforce encryption in transit (TLS) and at rest (KMS-managed keys) for all data movement and storage layers.
- Implement fine-grained access controls (e.g., Apache Ranger, AWS Lake Formation) based on role-based access policies.
- Audit all data access and pipeline execution events for compliance with SOX, GDPR, or HIPAA requirements.
- Mask or redact sensitive data in non-production environments used for migration testing.
- Validate that personally identifiable information (PII) is logged or stored only in approved, secured zones.
- Rotate credentials and API keys used in pipeline jobs on a scheduled basis with automated secret management.
- Conduct third-party security scans on pipeline code and infrastructure as code templates.
- Document data residency requirements and ensure target storage complies with geographic constraints.
Module 7: Change Management and Cutover Strategy
- Develop a phased cutover plan with parallel run periods to validate target system accuracy before decommissioning sources.
- Coordinate application reconfiguration timelines with development teams to switch from legacy to new data sources.
- Implement feature toggles to enable rollback to source systems in case of critical data defects post-migration.
- Freeze write operations on source systems during final delta sync to ensure point-in-time consistency.
- Communicate data downtime windows to business users and support teams with precise start and end times.
- Validate upstream and downstream dependencies (e.g., BI tools, ML models) against the migrated dataset before full cutover.
- Archive source system snapshots for a defined retention period to support post-migration audits or rollbacks.
- Update data catalog entries and lineage documentation to reflect new source locations and ownership.
Module 8: Post-Migration Operations and Monitoring
- Deploy automated anomaly detection on data freshness, volume, and schema to alert on pipeline failures.
- Establish SLAs for pipeline recovery time and data availability, and integrate with incident management systems.
- Conduct root cause analysis on data discrepancies reported by business users and update transformation logic.
- Optimize storage costs by implementing lifecycle policies to archive or delete stale data.
- Refresh statistics and metadata in the metastore after large data loads to maintain query planner efficiency.
- Review and refine pipeline performance quarterly based on usage patterns and data growth trends.
- Document operational runbooks for common failure scenarios and assign on-call responsibilities.
- Integrate data observability tools (e.g., Monte Carlo, DataDog) to monitor pipeline health and data quality trends.
Module 9: Governance, Metadata, and Long-Term Sustainability
- Implement automated metadata extraction to capture technical lineage from source to target across all pipeline stages.
- Standardize naming conventions and tagging policies for datasets, pipelines, and cloud resources.
- Establish data ownership and stewardship roles for migrated datasets with documented escalation paths.
- Integrate with enterprise data catalog tools to enable searchability and impact analysis.
- Define retention and archival policies for raw, staged, and transformed data layers based on legal and business needs.
- Conduct periodic data quality scorecard reviews with business units to prioritize improvement initiatives.
- Version control all pipeline code, configuration, and schema definitions using Git with peer review workflows.
- Plan for schema evolution by implementing schema registry tools (e.g., Confluent, AWS Glue Schema Registry).