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MySQL COUNT结果在RoR中被解释为字符串而不是整数

activerecord ruby-on-rails mysql

Steven · 技术社区 · 14 年前

这是我对好奇者的疑问。只有第一行和最后一行应该涉及这个问题:

SELECT s.parent_id AS id, COUNT(s.parent_id) as count
  FROM items i
  LEFT OUTER JOIN (SELECT item_id, user_id, MAX(created_at) as created_at
    FROM item_views iv
    WHERE iv.user_id = ?
    GROUP BY item_id) AS v ON i.id = v.item_id
  LEFT OUTER JOIN categories c ON c.id = i.category_id
  INNER JOIN (SELECT node.id AS node_id, parent.title AS parent_title, parent.id AS parent_id
    FROM categories AS node, categories AS parent
    WHERE node.lft BETWEEN parent.lft AND parent.rgt) s ON s.node_id=i.category_id
  WHERE (i.updated_at > v.created_at OR v.created_at IS NULL)
  AND i.updated_at > ?
  GROUP BY s.parent_id;

当我用 find_by_sql count 列似乎是字符串 "1" to_i