When lines are overwritten in cassandra

Question

My understanding is that rows are overwritten when another row with identical primary keys is inserted.

For instance:

I have columns (user_id int, item_id int, site_id int), and minePRIMARY KEY(user_id, item_id)

If I had the following table:

user_id, item_id, site_id
   2       3        4

and I insert user_id : 2, item_id : 3, site_id : 10, my new table will be:

user_id, item_id, site_id
   2       3        10

not

user_id, item_id, site_id
   2       3        4
   2       3        10

Is this simple case true in all cases? Are there any subtleties that I probably don't know? In addition, I could not find it in the documents and came to this conclusion, playing with cassandra, can anyone provide a source for the document?

Answer 1

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