Skip to main content

ERD Visualization

The ERD (Entity-Relationship Diagram) canvas is the visual centerpiece of TalkingSchema.

ActionHow
PanClick and drag on empty canvas space
Zoom in/outScroll wheel or pinch gesture
Fit to viewClick the fit-to-view button (bottom-left controls)
Reset zoomDouble-click on empty canvas space

Table nodes​

Each table appears as a node showing:

  • Table name (header)
  • Fields list — name, type, and constraint badges
  • PK badge — marks the primary key
  • FK badge — marks foreign key fields

Table header color​

You can set a custom background color on any table's header. Open the table editor and choose a color from the Header Color picker (or enter a hex value directly). The text color auto-adjusts for contrast so the header stays readable.

In DBML, this is serialized as:

Table orders [headercolor: #3b82f6] {
  ...
}

Relationship lines​

  • Lines connect tables via foreign keys
  • Crow's foot notation shows cardinality
  • Lines update automatically when you add/remove relationships

Relationship color​

Relationship lines can carry a custom color. The AI may set colors automatically to help distinguish relationship groups. In DBML this is:

Ref: orders.customer_id > customers.id [color: #79AD51]

The custom color is the resting stroke. On hover or when a connected table is selected, the line highlights in teal.

Table groups​

Tables can be organized into named groups that appear as labeled color overlays on the canvas. Groups help visually separate subsystems (e.g. Auth, Billing, Core).

Setting a group color​

When creating or editing a group, open the Group Color picker in the modal and choose a hex color or select from the preset swatches. The canvas overlay uses that color for both the background fill (at low opacity) and the border.

In DBML:

TableGroup "Auth" [color: #8b5cf6] {
  users
  sessions
}

If no color is set, groups cycle through a built-in palette of 10 colors.

ELK auto-layout​

TalkingSchema uses the ELK (Eclipse Layout Kernel) layout engine to automatically arrange table nodes. The layout:

  • Minimizes edge crossings
  • Groups related tables
  • Adapts when tables are added or removed

The layout runs automatically after AI changes. You can also manually drag nodes to your preferred positions.

Node visibility panel​

Use the node visibility panel to show/hide specific tables:

  • Toggle visibility per table
  • Useful for focusing on a subset of a large schema
  • Hidden tables are excluded from image exports

Exporting the diagram​

Click Export → Image to download:

  • PNG — raster image, good for presentations
  • SVG — vector, scalable, good for documentation
  • PDF — print-ready format

Only visible tables are included in the export.

Large schemas​

For schemas with many tables:

  • Use the node visibility panel to focus on relevant sections
  • Export section-by-section for documentation
  • Use the search/filter capability to find specific tables