SQL查询和联接表

Question

I am given an array of group IDs.
I have a table that has these integer fields:

id, node_id and group_id

In this table, node_id is not unique and group_id is not unique.

I need to locate each unique nodeID that has all of the given groupIDs . (I want just one instance of each node_id .)

//????
$groups_str = implode(',', $groups);
$query = "SELECT node_id FROM group_nodes
WHERE ............ IN({$groups}) 
...........";

Answer 1

SELECT node_id 
FROM group_nodes
WHERE group_id IN ($groups)
group by node_id
having count(distinct group_id) = $arraySize