agreed.

the idea of a relational database is to vastly reduce the amount of stored data by keeping it separate and unique.

get a copy of microsoft access (even a very old copy) and look at the...

depends on what you want to keep around.
if the data is not important for future reference, the delete cascade to your heart's content.

however, should data be valuable later, then those tables...

it is (almost) always a bad idea to have fields like item1, item2, item3... etc. as 1, it is not normal, and 2, you either have to few or too many columns.

ramymahrous above, offers a practical...