ERD Tables Reference
Reference for ERD table representations in NeoArc Studio: Data Views in persistence mode (recommended) and standalone ERD table shapes in the diagram editor (for freeform diagramming).
Two approaches are available for visualising entity-relationship data. Data Views in persistence mode are the recommended approach for structured data modelling, displaying entities as nodes on an interactive graph canvas with the Entity Overlay for property inspection. Standalone ERD table shapes in the diagram editor remain available for freeform diagramming.
| Approach | File Type | Source of Truth | Use Case |
|---|---|---|---|
| Data Views (Persistence Mode) | .data-view.json (fileType: "data-view") | Central model (model.neoarc) | Structured data modelling with database profiles, type resolution, Entity Overlay, and synchronised views |
| Standalone ERD Table Shapes | .diagram.json (diagramType: "standard") | Diagram file itself | Quick sketches, one-off diagrams, and freeform diagramming without a central model |
Data Views (Persistence Mode)
Data Views in persistence mode display model entities as nodes on a force-directed graph canvas. Click any node (or press Alt+Enter) to open the Entity Overlay, which shows the full property table with ERD-style columns. Entity properties, key roles, relationships, and constraints come from the model; the view file stores layout and profile configuration only.
| Feature | Description |
|---|---|
| Database profile selection | Each view references a databaseProfileId for vendor-specific type and name resolution |
| Entity picker | Select model entities to include, with group filtering and a 50-entity cap |
| FK edge inference | Connections between tables are inferred from foreign key relationships in the model |
| Type resolution | 12 abstract types resolve to concrete types via parameterised templates |
| Naming conventions | 11 case formats convert names to match vendor standards (PascalCase, snake_case, etc.) |
| Fidelity warnings | Confirmation dialog when switching profiles detects type fidelity loss |
| Auto-layout | ERD Left-to-Right and ERD Top-Down algorithms |
| Style overrides | Per-shape fillColor, borderColor, textColor, and headerFillColor |
| Canvas settings | Grid type (dot/line/none), grid size, snap-to-grid, default path type |
For the complete Data View document schema, see the Data View Document Reference page. For creating and configuring Data Views, see the Data Views guide.
Standalone ERD Table Shapes
The standard diagram editor includes standalone ERD table shapes for freeform entity-relationship diagramming. These shapes store their data directly in the diagram file without referencing a central model.
Table Structure
Each standalone ERD table shape displays the following elements.
Column Properties
| Property | Type | Description |
|---|---|---|
| name | string | Column name |
| type | string | Data type (varchar, int, datetime, etc.) |
| isPrimaryKey | boolean | Primary key flag |
| isForeignKey | boolean | Foreign key flag |
| isNullable | boolean | Nullable flag |
| description | string | Column description |
Creating Standalone ERD Tables
Relationships and Crow's Foot Notation
Connect standalone ERD tables using connections with crow's foot line endings to show cardinality.
| Line Ending | Meaning |
|---|---|
| crowsfoot-one | Exactly one |
| crowsfoot-many | Many |
| crowsfoot-zero-one | Zero or one (optional) |
| crowsfoot-zero-many | Zero or many |
| crowsfoot-one-many | One or many (required) |
Row-Level Ports
Standalone ERD tables support row-level ports, allowing connections to attach to specific columns rather than the table edge. Hover over a column to see available port indicators, then drag from the port to create a connection.
FK Auto-Fill
The FK Auto-Fill feature identifies potential foreign key relationships between selected standalone ERD tables based on column names and types.
SQL Server Import (Standalone)
The SQL Server import feature reads an existing database schema. In the standalone diagram context, the import creates ERD table shapes directly on the canvas with columns, data types, keys, and relationships.
ERD Linting
The standalone ERD linter validates diagrams with three severity levels.
| Severity | Description |
|---|---|
| Error | Critical issues requiring attention (missing primary keys, invalid references) |
| Warning | Potential problems to review (orphaned tables, relationship problems) |
| Info | Suggestions for improvement (naming convention violations) |
Export Options
| Format | Use Case |
|---|---|
| JSON | Full diagram document for version control |
| SVG | Vector export for documentation |
| CSV | Table structures for data dictionaries |
Auto-Layout
| Layout | Description |
|---|---|
| ERD Left-to-Right | Hierarchical layout with primary tables on the left |
| ERD Top-Down | Vertical hierarchical layout |