If power goes in middle , There is NO risk for loosing saved datas.Because The data is already stored in your hard disk.so that nothing to worry about that.
If you does not saved the data means,there is a problem that you might lost your unsaved data.
So there is always save your data when begin to work and repeat this after you finish some portion of data.If power goes off,There is lose for your final small portion.
Keep this tip and save your work.
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