I have the following tables:

cards
uploads
tags
tag_upload: Relation between a tag and an upload.
card_tag: Relation between a tag and a card.

Card 1 has a relation to the tags "event", "rmc", and "patient".

Upload 1 has a relation to the tags "event" and "patient".

Upload 2 has a relation to the tags "event", "rmc", and "patient".

Query 1:

I've selected the tags "event" and "patient".

It should return Upload 1, Upload 2, and Card 1.

Query 2:

I've selected the tags "event", "rmc", and "patient".

It should return Upload 1 and Card 1.

The Problem:

I'm currently using the following but when I do this Query 2 returns the same as Query 1:

What would the query look like that would select a card if it had the tags in it? Could I see an example or logic flow you might use?

This is my first version trying to get what I want down. Will be turned into testable code right after with PHPSpec.

Solution

Thank you eggyal!

SELECT *
FROM(
    SELECT   cards.id, cards.name, cards.type,
             cards.updated_at, cards.created_at, cards.image
    FROM     cards
        JOIN card_tag ON card_tag.card_id = cards.id
        JOIN tags     ON card_tag.tag_id  =  tags.id
    WHERE    NOT tags.deleted
         AND cards.type NOT IN ('','libraries')
         AND cards.account_user_id = 1
         AND tags.name IN ('rmc', 'test')
    GROUP BY cards.id
    HAVING   COUNT(DISTINCT tags.id) = 1
UNION ALL
    SELECT   uploads.id, uploads.name, uploads.type,
             uploads.updated_at, uploads.created_at, uploads.image
    FROM     uploads
        JOIN tag_upload ON tag_upload.upload_id = uploads.id
        JOIN tags     ON tag_upload.tag_id  =  tags.id
    WHERE    NOT tags.deleted
         AND uploads.type NOT IN ('','libraries')
         AND uploads.account_user_id = 1
         AND tags.name IN ('rmc','test')
    GROUP BY uploads.id
    HAVING   COUNT(DISTINCT tags.id) = 2
) AS qry
    ORDER BY `updated_at` DESC
    LIMIT 0, 35

详解该语句（这个是根据学号查找的语句）

baidu_29643173

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