# Bus Matrix

> The master plan of the data warehouse. Updated throughout the modelling process.
> Each row = a business process (fact table). Each column = a dimension.
> A ✓ indicates that dimension is used by that process.
> Dimensions appearing in multiple rows are **conformed dimensions**.

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## Bus Matrix

| Business Process | Date | [Dim 2] | [Dim 3] | [Dim 4] | [Dim 5] | [Dim 6] | [Dim 7] | [Dim 8] |
|---|---|---|---|---|---|---|---|---|
| [Process 1] | ✓ | | | | | | | |
| [Process 2] | ✓ | | | | | | | |
| [Process 3] | ✓ | | | | | | | |

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## Conformed Dimensions

> Dimensions that appear in more than one row require a single agreed definition and shared implementation.

| Dimension | Used by (processes) | Owner | Status | Notes |
|---|---|---|---|---|
| Date | All | Data team | Conformed | Standard date dimension |
| | | | `conformed / in-progress / contested` | |

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## Build priority

> Derived from the bus matrix. High-tick dimensions deliver the most cross-process analytical value.

| Dimension | Tick count | Priority | Rationale |
|---|---|---|---|
| Date | All | 1 — build first | Universal |
| | | | |

| Fact Table | Connected dimensions | Priority | Rationale |
|---|---|---|---|
| | | | |

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## Open conflicts

> Dimensions or processes where definition or ownership is unresolved.

| Item | Conflict description | Parties involved | Resolution owner | Status |
|---|---|---|---|---|
| | | | | |

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## Version history

| Version | Date | Changes | Author |
|---|---|---|---|
| v0.1 | | Initial draft from research (pre-interviews) | |
| v0.2 | | Updated after [role] interviews | |
| v1.0 | | Signed off by stakeholders | |