仅获得具有特定联接表计数的用户

Question

My SqlFiddle

Seems pretty simple but for the life of me I cannot seem to get the results I want. Keep in mind this is happening on a server that has over 6 million records so it has to be efficient.

I want to get the users who are joined to item table that have status 1 of 3 count or higher only not the users who have status of 1 on an item 2 times has to be >= 3.

SELECT 
    user.id,
    user.name,
    item.id as item_id,
    itemstatus.item_status,
    COUNT(item.status) as status
FROM user
JOIN item ON (user.id = item.user_id)
JOIN itemstatus ON (item.status = itemstatus.id)
WHERE item.status = 1
GROUP BY user.id

My current query above get all with a count. How do I get only the ones that have the 3 or above count. Thanks in advance. I hope I made this clear.

Answer 1

If I understand you correctly, you only want records with COUNT(item.status) greater than or equal to 3, in which case you need to use the HAVING clause after your GROUP BY clause. The HAVING clause is sort of like a WHERE clause for aggregate values.

SELECT 
    user.id,
    user.name,
    item.id as item_id,
    itemstatus.item_status,
    COUNT(item.status) as status
FROM user
JOIN item ON (user.id = item.user_id)
JOIN itemstatus ON (item.status = itemstatus.id)
WHERE item.status = 1
GROUP BY user.id
HAVING COUNT(item.status) >= 3