如何獲取布爾結果SQL查詢

Question

我正在嘗試創建一個SQL查詢，該查詢將返回imageId，此圖像的喜歡總數，以及當前用戶是否喜歡該圖像的布爾值。

到目前為止，我有：

Select i.imageId, count(l.likeId) as numOfLikes
FROM Images as i LEFT JOIN Likes as l USING (imageID)
WHERE i.userId = '16'
GROUP BY i.imageId
ORDER BY i.dateCreated DESC

這對於imageIds和每個圖像的喜歡總數非常有用。 我不確定如何確定用戶是否喜歡同一查詢中的圖像。

提前致謝！

Answer 1

這樣的事情應該起作用。

Select i.imageId, count(l.likeId) as numOfLikes
, count(likes2.*) LikesByUser
FROM Images as i LEFT JOIN Likes as l USING (imageID)
left join likes likes2 using (imageID, UserId)
WHERE i.userId = '16'
GROUP BY i.imageId
ORDER BY i.dateCreated DESC

LikesByUser應該為0或1。