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Mysql 多对多select语句不正确_Mysql_Sql - Fatal编程技术网

Mysql 多对多select语句不正确

Mysql 多对多select语句不正确,mysql,sql,Mysql,Sql,我注意到我的sql查询中有一个错误,但我不确定我做错了什么: SELECT blog_posts.postid, blog_posts.posttitle, blog_posts.postdesc, blog_posts.postdate FROM blog_posts INNER JOIN members_posts ON members_posts.memberid = blog_posts

我注意到我的sql查询中有一个错误,但我不确定我做错了什么:

SELECT blog_posts.postid, 
       blog_posts.posttitle, 
       blog_posts.postdesc, 
       blog_posts.postdate 
FROM   blog_posts 
       INNER JOIN members_posts 
               ON members_posts.memberid = blog_posts.postid 
WHERE  members_posts.memberid = '1' 
在上面的例子中,我试图只选择属于memberID='1'的帖子。但是什么也没有显示

这是您的查询:

SELECT bp.postID, bp.postTitle, bp.postDesc, bp.postDate
FROM blog_posts bp INNER JOIN
     members_posts mp
     ON mp.memberID = bp.postID
-----------^ ------------^ That seems unlikely
WHERE mp.memberID = '1';
使用正确的列:

SELECT bp.postID, bp.postTitle, bp.postDesc, bp.postDate
FROM blog_posts bp INNER JOIN
     members_posts mp
     ON mp.postId = bp.postID
WHERE mp.memberID = 1;
此外:

  • 表别名使查询更易于编写和读取
  • 不要在数值常量周围加单引号
您注意到的“错误”是什么?您是看到错误消息还是只看到0行?查询本身不返回行不是错误。