SQLite As Application File Format - Undo/Redo
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A simple script automatically creates TRIGGERs that record all changes to tables in the database which is the application file
To undo/redo:
Replay relevant parts of the change log
Restore any Tcl variables saved in the change log
Repaint the screen based on new database content
A complete Undo/Redo module is a few hundred lines of Tcl code
Because the history file is in a database on disk, undo/redo histories can grow very large without consuming excess memory
Once written, the same Undo/Redo module can be reused for different applications!
