Visual cues at a glance
A quick reference table covering every visual signal in the diagram. Bookmark this if you're skimming. For the explanations behind each cue, follow the link in the rightmost column.
Containers
| What you see | What it means | More |
|---|---|---|
| Dashed-border box around entities | A container declaration (Schema, Database, Container, etc.) | Containers |
| Colored header band on the container | Identifies the container by its accent color | Containers |
| Keyword and name in the header | The container's keyword (Schema, Database, etc.) and its name | Containers |
→ EngineName on the right of the header | The target storage engine (Oracle, MongoDB, etc.) | Containers |
| All entities inside share a header color | They belong to the same container | Containers |
| Thicker blue outline on the container | The container is currently selected | Inspector pane |
Entity cards
| What you see | What it means | More |
|---|---|---|
| Card with header band and field rows | An entity (Table, Entity, Collection, Record) | Entity cards |
| Keyword in the header (small text) | "Table", "Entity", "Collection", or "Record" | Entity cards |
| Entity name in the header (large text) | The entity's declared name | Entity cards |
| Thicker blue card outline | The entity (or one of its fields) is currently selected | Inspector pane |
| Light blue row background | That field row is selected | Inspector pane |
| Blue strip on the left edge of a row | Selection accent on the selected field row | Inspector pane |
Field badges
| Badge | Color | What it means | Source setting |
|---|---|---|---|
| PK | Yellow | Primary key | [pk] or [primary key] |
| UNIQUE | Purple | Unique constraint | [unique] |
| REQUIRED | Red | Not nullable | [not null] or [required] |
| AUTO | Blue | Auto-increment | [increment] |
Composite primary keys show the PK badge on every member field, not just the first one.
Field row text
| What you see | What it means |
|---|---|
| Plain field name | A user-defined field |
| Italic field name | A synthetic row ([item], {alt}, <key>, <value>, <item>, [N]) that doesn't correspond to a user-written field |
| Type label right-aligned | The compact form of the field's type |
varchar(100), decimal(10,2) | A sized scalar type with parameters |
object {…} | An object type with sub-fields rendered as nested rows |
array of X | An array type; X is the element type's short form |
oneOf (n), anyOf (n), allOf (n) | A polymorphism with n alternatives |
map [K → V] | A map type from K to V |
set [X] | A set of X |
tuple (n) | A tuple with n positions |
Disclosure carets
| Caret | Meaning |
|---|---|
▾ (downward) | The parent row is expanded; children are visible. Click to collapse. |
▸ (rightward) | The parent row is collapsed; children are hidden. Click to expand. |
| No caret | Leaf field; no children to show. |
Carets only appear on rows whose field has structured-type children. See Nested fields.
Relationships
The curved line between two entities is a Ref:. Each endpoint carries a symbol indicating cardinality and optionality:
| Symbol | Cardinality | Reads as |
|---|---|---|
─║ | Exactly one | min=1, max=1 (mandatory, single) |
─○║ | Zero or one | min=0, max=1 (optional, exclusive) |
─≺ | One or many | min=1, max=* (mandatory, multiple) |
─○≺ | Zero or many | min=0, max=* (optional, multiple) |
The ring (○) means "zero allowed." The bar (║) caps "exactly one." The crow's foot (≺) means "many," with the V opening toward the entity. See Relationships & crow's foot notation.
When the line is blue and thicker, the relationship is currently selected.
Cardinality text labels (0..*, 1..1, etc.) appear next to the glyphs as the source of truth. Glyphs are the visual shorthand; text is exact.
Colors
| Color | Where it appears | What it means |
|---|---|---|
Blue (#2563eb) | Selection outlines, accents | Currently selected element |
| Yellow | PK badge | Primary key |
| Purple | UNIQUE badge | Unique constraint |
| Red | REQUIRED badge, error squiggles, diagnostics errors | Required field, or a parse error |
| Amber | Warning indicators, screenshot placeholders in help | Warning or todo |
| Grey | Type labels, cardinality text, indent guides | Subordinate information |
| Container accent colors | Container header bands, member entity header bands | Container identity (deterministic from name) |
Cursor states
| Cursor | Where | What it indicates |
|---|---|---|
| Default (arrow) | Empty canvas | No action available; click to deselect |
| Pointer (hand) | Anywhere clickable: entity headers, field rows, container bodies, relationship lines | Clickable to select |
| Grab / grabbing | Entity header band when held | Drag in progress |
| Col-resize | Pane dividers | Drag to resize the pane |
What's next
If you want the explanations behind the cues: