Mysql 在where子句中使用联接值

我想对联接表中的值使用where语句。无法理解：

SELECT item.*, count(articles.authorid) AS articlecount 
FROM #_authors AS item 
LEFT JOIN #_articles AS articles ON (articles.authorid = item.id) 
WHERE item.published=1 
AND articlecount>3 
ORDER BY articlecount DESC

orderby工作正常，但当我添加“AND articlecount>3”时，我得到了错误：“#1054-where子句”中的未知列“articlecount”

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什么是包含WHERE on Article Count的最佳方式？提前谢谢

尝试使用

have

按聚合值过滤：

 SELECT item.*, count(articles.authorid) AS articlecount 
    FROM #_authors AS item 
    LEFT JOIN #_articles AS articles ON (articles.authorid = item.id) 
    WHERE item.published=1 
    AND articlecount>3 
    ORDER BY articlecount DESC


articlecount refers to which table field?
if articlecount  is in #_author table then you have to write item.articlecount 

or articles.articlecount

WHERE item.published=1
HAVING count(articles.authorid) > 3
ORDER BY articlecount DESC 

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尝试使用

have

按聚合的valeus进行过滤：

WHERE item.published=1
HAVING count(articles.authorid) > 3
ORDER BY articlecount DESC 

---

对于聚合列，可以使用

HAVING

，如下所示：

SELECT item.*, count(articles.authorid) AS articlecount 
FROM #_authors AS item 
LEFT JOIN #_articles AS articles ON (articles.authorid = item.id) 
WHERE item.published=1 
GROUP BY 1,2,3,4,5,6,7,8 -- assuming there are 8 columns in item
HAVING count(articles.authorid) > 3 
ORDER BY 9 DESC -- assuming there are 8 columns in item

---

对于聚合列，可以使用

HAVING

，如下所示：

SELECT item.*, count(articles.authorid) AS articlecount 
FROM #_authors AS item 
LEFT JOIN #_articles AS articles ON (articles.authorid = item.id) 
WHERE item.published=1 
GROUP BY 1,2,3,4,5,6,7,8 -- assuming there are 8 columns in item
HAVING count(articles.authorid) > 3 
ORDER BY 9 DESC -- assuming there are 8 columns in item

---

articlecount不在表中，它是语句顶部计数的结果值。该计数在articles表中，但没有名为“articlecount”的数据库字段。这就是问题所在。articlecount不在表中，它是语句顶部计数的结果值。该计数在articles表中，但没有名为“articlecount”的数据库字段。这就是问题所在，它起作用了。在GroupBy之后添加“HAVING count（articles.authord）>3”就成功了！谢谢成功了。在GroupBy之后添加“HAVING count（articles.authord）>3”就成功了！谢谢