How to pull the total # of items from one sharepoint list as a column in another list?

Question

The site has a list (List A) that links to multiple comments lists. For each item in List A, a unique list exists to capture comments related to that item.

1. Users want to know how many comments have been logged on that item while in List A, without having to jump to the comments list.
2. If that is possible, then I'm sure next they will want to know how many new items were created in the comments list since last the user visited.

I would be ever so grateful if I could just get some guidance on the first question!

Thanks in advance!

Answer 1

1) I believe you are looking for the SPList.ItemCount property of the list.

2) For this, you will have to query the list and get the items whose "Created" column has a value between now and when the user last logged in.