php - 为什么 MySQL 语句被忽略？

Question

这个问题已经有答案了:

SQL JOIN and different types of JOINs (6 个回答)

已关闭 9 年前。

为什么是n.author='$host[id]'被忽略？

$host[id]=5;
SELECT  
n.id,n.name,n.text,
r.title,
COUNT(c.news_id) comments
FROM news n LEFT JOIN rub r
 ON
 r.news_id=n.id 
 LEFT JOIN comments c 
  ON 
n.id = c.news_id AND c.status='1' AND n.author='$host[id]'
GROUP BY n.id
 ORDER BY n.id DESC LIMIT 10

我只需要 'news'.'author'=$host[id] 的行，但执行此查询我从表中获取了所有新闻。为什么会发生这种情况？

Answer 1

$host[id]=5;

SELECT n.id,n.name,n.text, r.title, COUNT(c.news_id) comments
FROM news n 
LEFT JOIN rub r ON r.news_id = n.id 
LEFT JOIN comments c ON c.news_id = n.id AND c.status = '1'
WHERE n.author = '$host[id]'
GROUP BY n.id
ORDER BY n.id DESC LIMIT 10