php - mysql查询3个表

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此查询未选择，没有评论或没有投票数据，我该如何修复？

SELECT 
    blog_posts.*, 
    COUNT(DISTINCT(blog_comments.CommentID))  AS CountComments, 
    COUNT(DISTINCT(blog_votes.VoteID)) AS CountVotes,
    AVG(DISTINCT(blog_votes.Vote)) AS AvgVote 
    FROM blog_posts 
    INNER JOIN blog_comments ON blog_comments.CommentBlogID=blog_posts.BlogID 
    INNER JOIN blog_votes ON blog_votes.VoteBlogID=blog_posts.BlogID 
    ORDER BY blog_posts.BlogID
    LIMIT 0,10

Answer 1

我修好了

SELECT
blog_posts.*,
COUNT(VoteID) as CountVotes,
AVG(VoteID) As AvgVotes,
COUNT(CommentID) AS CountComments
FROM blog_posts
LEFT JOIN blog_votes ON blog_posts.BlogID = blog_votes.VoteBlogID
LEFT JOIN blog_comments ON blog_posts.BlogID = blog_comments.CommentBlogID
GROUP BY blog_posts.BlogID
ORDER BY BlogID DESC  
LIMIT 0,10