mysql - Like中的子查询字段

Question

我有以下查询：

SELECT
(...),
(SELECT us.short FROM url_short us WHERE us.urlId = u.id
  ORDER BY us.id DESC LIMIT 1) as short, 
(...),
(SELECT f.name FROM `group` f LEFT JOIN group_url fu ON f.id = fu.group_id WHERE
  fu.url_id = u.id ORDER BY f.id DESC LIMIT 1) as f_name
FROM (...)
WHERE (...) AND
(u.url LIKE '%ops%'
OR short LIKE '%ops%'
OR u.url_name LIKE '%ops%'
OR f_name LIKE '%ops%')
(...)

但是，当我尝试在short和f_groupMySQL 中使用 LIKE 时，我会说：

#1054 - Unknown column 'short' in 'where clause'

我已经搜索了很多，但一无所获

Answer 1

您的 where 子句看不到short别名，因为它仅通过在过滤结果集（由最外层子句实现）之后发生的投影步骤引入。WHERE

尝试

SELECT *
  FROM (
          SELECT
          (...),
          (SELECT us.short FROM url_short us WHERE us.urlId = u.id
            ORDER BY us.id DESC LIMIT 1) as short, 
          (...),
          (SELECT f.name FROM `group` f LEFT JOIN group_url fu ON f.id = fu.group_id WHERE
            fu.url_id = u.id ORDER BY f.id DESC LIMIT 1) as f_name
          FROM (...)
          WHERE (...)
       ) emb
   WHERE (emb.url LIKE '%ops%'
          OR emb.short LIKE '%ops%'
          OR emb.url_name LIKE '%ops%'
          OR emb.f_name LIKE '%ops%')
       ;

Answer 2

您在查询中使用别名，这可能会导致此错误。 这是另一个有类似问题的问题。