I am currently making a program. And I should make a complicated sql query, but I can’t do it. I have two tables
person:id etc
and
item id, personid foreign key value
There is a 1:N relationship between the two tables.
And for each person, how much of the items belonging to him should be calculated in a given value.
for example Person1 item with value 10 has 5 items, item with value 2 has 100 items.

I thought about it a lot, but I couldn’t find a solution. Anyone have any ideas? I use mysql dbase.