Key Design Considerations
1. Data Modeling
The foundation of any successful Analysis Services project lies in a well-designed data model. This involves understanding your business requirements and translating them into efficient cube structures.
- Dimensional Modeling: Embrace the star or snowflake schema for your data warehouse. This structure is highly optimized for analytical queries.
- Fact Tables: Choose the appropriate grain for your fact tables. A fine-grained fact table offers more detail but can lead to larger cube sizes.
- Dimension Design: Consider dimension types (standard, degenerate, slowly changing dimensions). Implement proper hierarchies for intuitive navigation.
- Measures: Define measures carefully, considering aggregation methods (Sum, Count, Average, Min, Max). Use calculated measures and KPIs to provide business-specific insights.
2. Performance Optimization
Performance is paramount for user adoption. Several factors influence how quickly users can explore data.
- Partitioning: Divide large fact tables into smaller, manageable partitions based on time or other criteria. This improves query performance and management.
- Aggregation Design: Pre-calculate aggregations for frequently accessed data combinations. This significantly speeds up query responses. Use the Aggregation Design Wizard or custom aggregation strategies.
- Indexing: While not explicit in Analysis Services, the underlying data warehouse indexing strategy plays a crucial role. Ensure fact and dimension tables are appropriately indexed.
- Query Optimization: Write efficient MDX queries. Avoid large sub-cube operations where possible.
3. Scalability and Manageability
Design for growth and ease of maintenance.
- Hardware Resources: Allocate sufficient CPU, RAM, and fast I/O for your Analysis Services instance.
- Instance Sizing: Plan for future data growth and user concurrency.
- Deployment Strategy: Utilize project-based development with Visual Studio and deploy using XMLA scripts or deployment utilities.
- Backup and Restore: Implement a robust backup strategy for your databases.
4. Security Considerations
Protect your sensitive data and ensure users have appropriate access.
- Role-Based Security: Define roles with specific permissions on cubes, dimensions, and cells.
- Row-Level Security: Implement security at the row level within dimensions to restrict data visibility based on user attributes.
- Server Roles: Assign administrative privileges carefully.
5. User Experience
Make it easy for users to interact with the data.
- Intuitive Hierarchies: Structure dimension hierarchies logically.
- Clear Naming Conventions: Use descriptive names for cubes, dimensions, attributes, and measures.
- Action/Action-Based Calculations: Embed drill-through actions or URLs to provide deeper insights or navigate to related content.
Example Cube Structure (Conceptual)
Cube: SalesCube
Dimensions:
- DimDate (Date Hierarchy: Year -> Quarter -> Month)
- DimProduct (Product Hierarchy: Category -> Subcategory -> Product)
- DimCustomer (Customer Hierarchy: Country -> City -> Customer)
- DimSalesTerritory
Fact Table: FactSales
- Grain: One row per product sale transaction
Measures:
- [Total Sales Amount]: SUM(FactSales.SalesAmount)
- [Quantity Sold]: SUM(FactSales.OrderQuantity)
- [Average Sale Price]: AVG(FactSales.SalesAmount)
- [Number of Orders]: COUNT(DISTINCT FactSales.OrderID)
Calculated Measures:
- [Sales Growth %]: ([Total Sales Amount] - PREVIOUSQUARTER([Total Sales Amount])) / PREVIOUSQUARTER([Total Sales Amount])