Is there any efficient way to update the modified data from .csv file to database?
you will have to upload it, even if it's to a "upload" table which you then compare row by row to your main table to see what the differences are
why are you making changes in the csv? you should be making them to your main table
i guess i could turn the question around and ask you, if you made changes to the csv, but also kept a copy of the original csv, how easy is it for you to compare the two csv files and keep only the changed rows?