System Diagram

The Road Maintenance data model, mapped — 25 models, 50 relationships

🔍 For serious exploration, open the Interactive Diagram Viewer — it adds pan, mouse-wheel zoom, fit-to-screen, full-screen mode, a full ERD, and a focus mode that draws just one model and its neighbours at a chosen depth. The diagrams below are the readable, static summary.

Architecture Overview

The model has three layers: the network register (where work happens), the reference library (the rules of the guideline), and operational records (the work itself). The overview shows the principal links only — every arrow means "one row of the left model is referenced by many rows of the right model".

flowchart LR
    subgraph NET["🗺️ Network register"]
        District --> Network --> Road --> RoadSection --> RoadLocation
    end

    subgraph REF["📚 Reference library"]
        MaintenanceElement --> DefectType --> DefectSubType
        DefectSubType --> InterventionRule
        MaintenanceElement --> MaintenanceActivity --> ActivityStandard
        DefectSubType --> ValidDefectActivity
        MaintenanceActivity --> ValidDefectActivity
    end

    subgraph OPS["🔧 Operational records"]
        Inspection --> DefectObservation --> DefectAssessment --> DefectLogEntry --> DefectBacklog
        DefectObservation --> PlannedWork --> WorkOrder --> WorkExecution
        WorkOrder --> CompletionInspection --> DefectClosure
    end

    RoadSection --> Inspection
    InterventionRule --> DefectAssessment
    MaintenanceActivity --> WorkOrder

Module 1: Network Register

Where work happens — the road hierarchy from district down to a pinpoint location. RoadCategory (from the reference library) classifies roads and sections.

erDiagram
    District ||--o{ Network : "district_id"
    District ||--o{ Road : "district_id"
    Network ||--o{ Road : "network_id"
    Road ||--o{ RoadSection : "road_id"
    RoadSection ||--o{ RoadLocation : "road_section_id"
    RoadCategory ||--o{ Road : "road_category_id"
    RoadCategory ||--o{ RoadSection : "road_category_id"

Module 2: Reference Library

The rules of the guideline — defect taxonomy, intervention rules, activities and standards. A new guideline edition is a data load into these tables, not a software release.

erDiagram
    MaintenanceElement ||--o{ DefectType : "maintenance_element_id"
    DefectType ||--o{ DefectSubType : "defect_type_id"
    MaintenanceElement ||--o{ MaintenanceActivity : "maintenance_element_id"
    MaintenanceActivity ||--o{ ActivityStandard : "maintenance_activity_id"
    DefectSubType ||--o{ InterventionRule : "defect_sub_type_id"
    RoadCategory ||--o{ InterventionRule : "road_category_id"
    CorporatePriority ||--o{ InterventionRule : "corporate_priority_id"
    DefectSubType ||--o{ ValidDefectActivity : "defect_sub_type_id"
    MaintenanceActivity ||--o{ ValidDefectActivity : "maintenance_activity_id"
    RoadCategory ||--o{ ValidDefectActivity : "road_category_id"
    UnitOfMeasurement ||--o{ DefectSubType : "unit_of_measurement_id"
    UnitOfMeasurement ||--o{ InterventionRule : "unit_of_measurement_id"
    UnitOfMeasurement ||--o{ MaintenanceActivity : "unit_of_measurement_id"

Module 3: Operational Records (Defect Lifecycle)

The work itself: inspect → observe → assess → log → plan → order → execute → verify → close, with the governed backlog as the funding-constrained side exit.

erDiagram
    Inspection ||--o{ DefectObservation : "inspection_id"
    DefectObservation ||--o{ DefectAssessment : "defect_observation_id"
    DefectAssessment ||--o{ DefectLogEntry : "defect_assessment_id"
    DefectObservation ||--o{ DefectLogEntry : "defect_observation_id"
    DefectLogEntry ||--o{ DefectBacklog : "originating_log_entry_id"
    DefectObservation ||--o{ DefectBacklog : "defect_observation_id"
    DefectObservation ||--o{ PlannedWork : "defect_observation_id"
    PlannedWork ||--o{ WorkOrder : "planned_work_id"
    WorkOrder ||--o{ WorkExecution : "work_order_id"
    WorkOrder ||--o{ CompletionInspection : "work_order_id"
    CompletionInspection ||--o{ DefectClosure : "completion_inspection_id"
    WorkOrder ||--o{ DefectClosure : "work_order_id"
    DefectObservation ||--o{ DefectClosure : "defect_observation_id"

Cross-module references not drawn above (see the Full ERD in the interactive viewer): operational records also reference the network register (RoadSection and RoadLocation on observations, inspections, planned work and work orders) and the reference library (DefectSubType on observations; InterventionRule and CorporatePriority on assessments; MaintenanceActivity and ActivityStandard on planned work and work orders; UnitOfMeasurement on observations, planned work and executions).

Reading the Diagrams

  • A ||--o{ B means one row of A is referenced by many rows of B (the label is the foreign-key column on B).
  • Arrows in the overview point the same way: parent → children.
  • The three-layer split matches the sidebar menu grouping in the app.

Diagrams are derived from the generated schema metadata (apps/road_maintenance/generated/json/road_maintenance_relationship_metadata.json). If the DSL schema changes, regenerate that metadata and update this page and the viewer's embedded data.