# Master Data
> [!info] Core Concept
> Master Data is an **operational database** that serves as a centralized hub for managing critical reference data, lists, lookups, budgets, and other business-maintained information within the data platform. Unlike source systems or analytical layers, Master Data is actively managed by business users and provides a bidirectional interface with the [[Analytical Data Store (ADS)]].
## Purpose
Master Data serves several key functions in the data architecture:
| Function | Description |
|----------|-------------|
| **Centralized reference data management** | Single source of truth for business-critical lists, hierarchies, and classifications |
| **User-maintained lookups** | Business users maintain mappings and categories without IT intervention |
| **Budget and target management** | Upload and maintain budgets, targets, KPIs, and planning data |
| **Data enrichment** | Additional context and attributes joined with source system data |
| **Manual data entry** | Supports scenarios where data doesn't exist in source systems |
## Characteristics
### Operational Nature
Master Data is fundamentally different from other data platform layers:
| Characteristic | Description |
|----------------|-------------|
| **User-facing application** | Exposed through user-friendly interfaces (web apps, custom forms, file uploads) |
| **Transactional** | Supports CRUD operations (Create, Read, Update, Delete) by business users |
| **Version-controlled** | Includes temporal tracking to understand how reference data changes over time |
| **Governed** | Data ownership, approval workflows, and change tracking |
### Integration with Data Platform
Master Data maintains a bidirectional relationship with the Analytical Data Store (ADS):
```mermaid
%%{init: { "flowchart": { "useMaxWidth": true } } }%%
graph LR
MD[Master Data]
CONF[Analytical Data Store (ADS)]
MD -->|Enrichment Flow<br/>Reference data adds context| CONF
CONF -->|Feedback Flow<br/>New values flagged for classification| MD
classDef highlight stroke-width:2px
class MD,CONF highlight
```
**Enrichment flow** (Master Data → ADS): Reference data is joined with ADS data to add business context
**Feedback flow** (ADS → Master Data): New values discovered in source systems can be flagged for classification in Master Data
## Common Use Cases
| Use Case | Examples |
| ------------------------------------ | ------------------------------------------------------------------------------------------------------------------------- |
| **Account and Cost Center Mappings** | Department hierarchies, Business unit groupings, Functional area classifications |
| **Product Categorization** | Market segments, Product families and sub-families, Strategic importance classifications, ABC analysis categories |
| **Budget and Target Management** | Annual budgets by department/product/time period, Sales targets, KPI thresholds and benchmarks, Workforce planning data |
| **Customer Segmentation** | Customer segments (Small, Medium, Large Enterprise), Industry classifications, Strategic customer flags, Lifecycle stages |
| **Manual Corrections and Overrides** | Currency exchange rates, Manual adjustments to automated classifications, Business rules that override system logic |
## Technologies/Implementations
### Plainsight's Master Data Hub
**[Master Data Hub: Workbook to SQL](https://marketplace.microsoft.com/en-us/marketplace/consulting-services/plainsightpro.masterdatahub_excelforsql?tab=Overview)** is Plainsight's Excel-based plugin for managing SQL databases through a familiar spreadsheet interface.
**Key benefits:**
- Manage database tables directly from Excel - No SQL knowledge required
- Built-in validation and data quality checks
- Version control and audit trail automatically maintained
- Familiar Excel interface for business users
- Direct integration with data platform databases
**Best for:** Medium to large-scale Master Data implementations where business users need self-service capabilities with enterprise-grade data management.
**Demo video:**
[](https://www.youtube.com/watch?v=W_g8K8FP0tI)
### SharePoint Lists + Power Apps
For smaller projects, **SharePoint Lists combined with Power Apps** provide a lightweight Master Data solution.
**Key benefits:**
- No additional license required (included with Microsoft 365)
- Quick to set up and deploy
- Built-in collaboration and approval workflows
- Power Apps provides custom UI on top of SharePoint data
- Version history and permissions management included
**Best for:** Small to medium projects with limited Master Data volume, basic validation requirements, and teams already using Microsoft 365.
**Example use cases:**
- Product category lookups
- Customer segmentation flags
- Budget input forms
- Simple reference lists
> [!tip] SharePoint + Power Apps Pattern
> Use SharePoint Lists as the data store and build a Power Apps interface for data entry. Connect your ETL processes to read from SharePoint via connectors or export to CSV for batch processing.
### Custom Applications
When out-of-the-box solutions don't fit, **custom applications** can be developed to meet specific Master Data requirements.
**Considerations:**
- Higher development and maintenance cost
- Full control over UI/UX and business logic
- Can integrate complex approval workflows
- Supports specialized data validation rules
- May be necessary for high-security or complex scenarios
**Best for:** Enterprise-scale implementations with unique business requirements, complex workflows, or specialized security needs that off-the-shelf solutions can't address.
## Related Topics
- [[Analytical Data Store (ADS)]] - The primary integration point for Master Data
- [[Star - Dimension Tables]] - How Master Data enriches dimensional models
- [[Data Layers and Modeling]] - Where Master Data fits in the overall architecture