Question

I would like to print a list of items from a database table, and together with each one, a little list (10 items max) of related subitems.

For example, I have these 2 tables:

ITEMS

id: integer
name: string


SUBITEMS

id: integer
name: string
item_id: integer

So, an item can have many subitems.

I would like to print something like this:

Item 1
this item has: subitem 1, subitem 2, subitem 3

Item 2
this item has: subitem 4, subitem 5, subitem 6

Item 3
this item has: subitem 2, subitem 4, subitem 7

How can this be done in SQL? Is this even possible?

Answer 1

If it’s MySQL then

select i.*, group_concat(si.name) as subitems
from items i
left join subitems si on si.item_id = i.id
group by i.id