Undo, Redo

You can move back to a previous editing state or forward to a later one.
The history keeps up to 2048 changes.

• Undo: Ctrl + Z (Windows/Linux) or ⌘ + Z (Mac)
• Redo: Ctrl + Shift + Z (Windows/Linux) or ⌘ + Shift + Z (Mac)

The toolbar carries the same two commands as Undo and Redo buttons, next to Time Travel.
They light up only when there is something to undo or redo. A readonly editor hides all three, and the shortcuts do nothing.

Undo and Redo apply only on the ERD tab. They are unavailable on the Visualization, Schema SQL, Code Generator, and Settings tabs.
The shortcuts are also inactive while Quick Search, Table Properties, Diff Viewer, the Auto Layout preview, or Time Travel is open.

The history lives in memory for the current session. It is not stored in the document, so reopening a diagram starts with an empty history.

What the History Records

Recorded:

• Tables and memos: add, remove, move, color, name and comment, memo text and size.
• Columns: add, remove, reorder, and every column option.
• Relationships: add, remove, and type change.
• Indexes and their columns.
• View position, zoom level, and the View Option toggles.
• Importing a file.

Not recorded:

• The database vendor and the database name.
• The Code Generator language, Table Name Case, and Column Name Case.
• The Schema SQL bracket type.
• Everything on the Settings tab.
• Zoom and pan on the Visualization tab in either mode, moving graph nodes or Flow cards, Tidy Up, the row display, and focusing on tables — see Flow Never Edits the Document.

Changing any of these cannot be undone.

Changes that arrive from another editor are not recorded either, so Undo reverts only your own. In a collaborative session each editor undoes its own changes, and a coding agent editing through the MCP server undoes its own with erd_undo.

One Gesture, One Step

Everything a single gesture dispatches becomes one history entry.
Pasting several tables and memos at once, or duplicating them with Alt + drag, is undone in a single step.

A continuous drag, canvas pan, zoom, pinch, or color change is buffered for about 200ms and lands as one entry too.
A drag that moves less than 20px in total is not recorded at all.

Typing in a cell or a memo is recorded per input rather than per gesture: each typed character, each paste, and each step of an IME composition is a step of its own.

Time Travel

Opens from the Time Travel button in the toolbar, next to Undo and Redo.
The button does nothing until the session has at least one recorded change.

Time Travel opens a separate, read-only copy of the diagram.
Drag the slider, or click anywhere on its track, to move through the whole edit history and preview each point. The slider's leftmost position is the state one step before the first recorded change, and it opens with the thumb on the current state.
The preview is inert: it draws a minimap, but you cannot pan, scroll, or edit it, and the real document stays untouched until you apply.

Press Apply to restore the selected point, or Cancel or Esc to leave the document unchanged.