Sometimes you might incorrectly modify lots of records with mass editing or importing. When this happens, you can Revert Mass Update, which allows you to revert back to the previous values. It is important to note that once executed, this action cannot be undone.
Path: Hamburger Menu > Database Management > Recent Changes
On the other hand, if you would like to revert an import, there are a few restrictions:
1. This operation cannot be undone once executed.
2. Field values updated by link and load, formula recalculation, and workflow will not be reverted.
3. Reverting an import will not trigger link and load, formula recalculation, and workflow.
Please also note that it is not suggested to revert mass update if:
1. The design on related field(s) has been changed.
2. The Mass Update was made a long time ago.
Some actions cannot be directly restored from the Recent Changes (e.g. Batch Execute Action Button). In such cases, you can refer to this article: "How to Recover Lost Field Values?"