User Guide
Entity Relationship Diagrams (ERD)
Build table-style ERDs like pro tools: entities (tables), fields (columns), and relationships (FK links). Toggle Crow’s Foot vs Chen notation and export SQL/PDF for documentation.
1) Add entities (tables)
- Drag Entity onto the canvas. Use Weak Entity when you want double-border styling.
- Double-click the header to rename the table.
2) Add/edit fields (columns)
- Select an Entity → use the Properties panel → add a new field.
- Edit field name and data type (e.g., uuid, int, varchar(255)).
- Toggle PK / FK / Nullable / Unique per field.
- For FK, select the referenced Entity and referenced PK field.
3) Connect entities (relationships)
- Drag from a handle on one entity to another to create a relationship edge.
- Use the toolbar toggle to switch Notation: Crow’s Foot vs Chen.
4) Import/Export
- Export JSON to share/re-import the ERD state later.
- Export SQL to generate PostgreSQL DDL from your entities + FK field references.
- Import SQL (reverse engineering): paste CREATE TABLE statements to generate entities and FK edges.
- Export PDF to get the diagram image + a data dictionary section.
5) Auto-layout
- Use Auto-Layout to place entities in a clean grid quickly.
- Then fine-tune by dragging; grid snapping is 15px to keep things aligned.
Troubleshooting
- If SQL import misses a constraint, share the DDL snippet and we’ll improve the parser.
- If edges overlap, run Auto-Layout, then manually space out highly connected tables.