Database organization

Another question regarding how to organize my database -

I have a comments system where each comment can be rated, so I want to store which comments a user rates (so I can limit how many times they rate the comment).

But putting an array of this size into a column seems kinda awkard - it’d be something like this (a column called ‘ratings’ or something in the users table):

2498869_0, 3452352_1, 343525_2…

Where the first set of numbers is the comment id and the 0, 1, or 2 is the rating they gave (0 meaning a downwards rating, 1 neutral, and 2 positive).

Is there any other way that would be better - 'cause that ratings column could be getting extremely long pretty fast…