Data Warehousing
Central architectural concept for collecting, integrating and historizing enterprise data to support analytics and reporting.
Classification
- ComplexityHigh
- Impact areaBusiness
- Decision typeArchitectural
- Organizational maturityIntermediate
Technical context
Principles & goals
Use cases & scenarios
Compromises
- Data inconsistencies with insufficient governance
- Excessive centralization can restrict agility
- Cost explosion from uncontrolled storage and compute growth
- Iterative rollout: core domains first, gradual expansion
- Introduce automated data quality monitoring
- Define clear responsibilities for data products
I/O & resources
- Source transactions from operational systems
- Master data and reference tables
- Metadata, schema definitions and business glossary
- Cleansed fact and dimension tables
- Data marts and query-optimized views
- Reports, dashboards and analytical datasets
Description
Data warehousing is an architectural concept for centralizing, integrating, and historizing large enterprise data from diverse sources. It enables analytics, reporting, and data-driven decisions through structured schemas, ETL/ELT processes, and semantic models. Typical implementations use data marts, star or snowflake schemas, and specialized warehouse systems.
✔Benefits
- Consistent, cleansed data foundation for analytics
- Improved performance for reporting workloads
- Support for historical analyses and compliance
✖Limitations
- High initial effort for modeling and ETL/ELT pipelines
- Possible latency between source and warehouse
- Scaling large, heterogeneous datasets requires planning
Trade-offs
Metrics
- Query latency (P95)
Time in which 95% of queries are answered; important for user experience.
- ETL run time
Total duration of data load and transformation processes; affects data freshness.
- Cost per TB and per query
Monetary metrics to evaluate storage and query costs.
Examples & implementations
Retail data warehouse for sales analytics
Central warehouse integrating POS, online store and inventory data to analyze sales trends and assortment efficiency.
Financial reporting platform
Consolidated financial dataset enables monthly, quarterly and annual closings on a unified data basis.
Marketing attribution warehouse
Combining campaign data and web events for attribution and campaign optimization.
Implementation steps
Stakeholder workshops to define goals and KPIs
Create source inventory and perform data profiling
Design logical and physical data model
Implement and automate ETL/ELT pipelines
Complete monitoring, testing and rollout planning
⚠️ Technical debt & bottlenecks
Technical debt
- Legacy ETL scripts without tests and documentation
- Ad-hoc partitioning and missing indexing strategy
- Monolithic schemas without modularization into data marts
Known bottlenecks
Misuse examples
- Using the warehouse as a replacement for operational OLTP systems
- Directly loading raw, uncleaned data without profiling
- Missing archival strategy leads to unaffordable costs
Typical traps
- Unclear ownership of data products
- Underestimating operational effort for ETL pipelines
- Neglecting security and access controls
Required skills
Architectural drivers
Constraints
- • Availability and quality of source system data
- • Budget for storage and compute capacity
- • Compliance and data protection requirements