Four tables wil be modified this weekend- Developer ask for backup prior to modifyng - rollback will

 Hi experts.  Four tables wil be modified this weekend. Developer ask for backup prior to modifyng.   The rollback will be importing back those tables. My question is, if I'am doing rollback, then the tables must be deleted prior to imporitng back the export done
before modification and then I don't know if I should delete cascade.
There are eleven tables that have a column named exactly as the primary key of those four tables.