Ruby on rails 在activerecord关系中从Rails 4.0升级到Rails 4.2后出错

根据官方文档，我已经从Rails4升级到Rails4.2

顺便说一下，我有一个bug需要修复

在我的搜索控制器中，我有：

@contents  = Content.published.search_by_text(@query)
  Content Load (248.7ms)  SELECT "contents".*, ((ts_rank(("contents"."tsv"), (to_tsquery('italian', ''' ' || 'ces' || ' ''')), 0))) AS pg_search_rank FROM "contents" WHERE "contents"."state" = $1 AND (published_at <= '2015-04-07 16:38:38.000591') AND ((("contents"."tsv") @@ (to_tsquery('italian', ''' ' || 'ces' || ' '''))))  ORDER BY published_at DESC, pg_search_rank DESC, "contents"."id" ASC  [["state", "published"]]

=> []

@contents.count
PG::SyntaxError: ERROR:  syntax error at or near "AS"

我添加到_a，现在它可以工作了

@contents.to_a.count
=> 0

---

我想了解为什么需要将活动记录查询的结果转换为数组。Rails 4.2中发生了什么变化？

您可以在这里查阅变更日志：试试@contents.count（：all）谢谢@DannielR它可以工作了

@contents.to_a.count
=> 0