ER Diagram
The ER Diagram viewer generates a live, interactive entity-relationship diagram directly from your database schema. Tables appear as nodes; foreign key relationships appear as edges connecting them. The layout is computed automatically using the Dagre graph layout engine.
Opening the ER Diagram
Right-click a database or schema in the sidebar and choose Open ER Diagram. The diagram opens in a new window dedicated to that connection and schema.
Interface
The diagram window has a minimal header with:
- Connection / Database / Schema — shown at the top so you always know which schema you're viewing.
- Refresh button — re-fetches the schema from the database and redraws the diagram.
- Fullscreen toggle — expands the diagram to fill the entire display. Press
Escto exit.
Nodes
Each table is a node showing:
- Table name (header)
- Column list with data types
- Primary key indicator
- Foreign key indicator (columns that participate in a relationship)
Edges
Foreign key constraints are drawn as directed edges from the referencing column to the referenced table. The direction follows the FK definition — the arrow points from the child (referencing) table to the parent (referenced) table.
Navigation
| Action | Result |
|---|---|
| Scroll wheel | Zoom in / out |
| Click + drag (on canvas) | Pan the view |
| Click + drag (on a node) | Move the node to a custom position |
| Double-click (on canvas) | Reset zoom and center the diagram |
Layout Options
Tabularis supports two Dagre layout directions, configurable in Settings → General:
| Setting | Description |
|---|---|
TB (Top-Bottom) |
Tables are laid out from top to bottom — works well for tall schemas with many relationships. |
LR (Left-Right) |
Tables flow left to right — better for wide schemas with fewer levels. |
The setting is stored as erDiagramDefaultLayout in config.json. Changing it and reopening the diagram applies the new layout.
Refreshing the Schema
The ER Diagram reads the schema at the time you open it. If you modify tables (add columns, create foreign keys) while the diagram is open, click Refresh to reload the schema and redraw the diagram with the latest structure.
Supported Relationships
| Database | FK Support |
|---|---|
| PostgreSQL | Full — all FK constraints in information_schema are shown. Multi-schema FK relationships are included when available. |
| MySQL / MariaDB | Full — FK constraints from information_schema.KEY_COLUMN_USAGE and REFERENTIAL_CONSTRAINTS. |
| SQLite | Partial — FK constraints are shown only if PRAGMA foreign_keys is enabled in the database file. |
| Plugin drivers | Depends on whether the plugin implements the get_foreign_keys method in its manifest. |
Export
The ER Diagram window does not currently offer a dedicated export button. To save a snapshot:
- macOS: Use
Cmd + Shift + 4to take a screenshot of the window. - Windows: Use
Win + Shift + S(Snipping Tool). - Linux: Use your desktop environment's screenshot tool.
Alternatively, use the Fullscreen mode before screenshotting for a larger, cleaner capture.
Notes
- The ER Diagram opens in a separate window. You can keep it open alongside the main Tabularis window while working in the SQL editor.
- For very large schemas (100+ tables), the initial layout may take a moment to compute. Dragging nodes manually after the initial render is a good way to organize dense clusters.
- Node positions are not persisted — each time you open the diagram, Dagre recalculates the layout from scratch.