MySQL查询有什么问题？

Question

SELECT n.nid, n.title, c.field_news_date_value, 
       c.field_news_short_text_value, c.field_news_short_text_format 
FROM node n, term_data m,  term_node p 
INNER JOIN content_type_news c 
   ON c.nid = n.nid AND c.vid = n.vid 
WHERE n.type='news' AND n.status=1 
ORDER BY c.field_news_date_value DESC.

我收到一个错误

“ on子句”中的未知列“ n.nid”。

Answer 1

我认为查询必须是这样的。 （假设两个表中都必须有列，名称分别为nid和vid ）

注意：使用JOIN时在FROM子句中使用多表是不明确的

SELECT n.nid, n.title, c.field_news_date_value, 
       c.field_news_short_text_value, c.field_news_short_text_format 
FROM node n
INNER JOIN content_type_news c 
ON c.nid = n.nid AND c.vid = n.vid 
WHERE n.type='news' AND n.status=1 
ORDER BY c.field_news_date_value DESC.

Answer 2

尝试这个：

SELECT n.nid, n.title, c.field_news_date_value, c.field_news_short_text_value, c.field_news_short_text_format 
FROM term_data m, term_node p, node n INNER JOIN content_type_news c 
ON c.nid = n.nid AND c.vid = n.vid 
WHERE n.type='news' AND n.status=1 
ORDER BY c.field_news_date_value DESC

基本上，将node n移动到INNER JOIN运算符附近。

Answer 3

您需要在查询中使用AS 。 请使用以下查询：

SELECT 
 n.nid, n.title, 
 c.field_news_date_value, 
 c.field_news_short_text_value, 
 c.field_news_short_text_format 
FROM 
 node as n, term_data as m,  term_node as p 
INNER JOIN 
 content_type_news c ON c.nid = n.nid AND c.vid = n.vid 
WHERE 
 n.type='news' 
 AND n.status=1 
ORDER BY 
 c.field_news_date_value DESC