Question

我找不到如何用rom-sql编写此查询的方法。可以将纯SQL添加到where吗？

它查找与请求不相交的公告。 announcements.when和requests.when是postgres中的tstzrange列。

SELECT "announcements".* FROM "announcements" WHERE (
  (SELECT COUNT(requests.id)
   FROM requests
   WHERE requests.id IN (1,2,3) AND
         (TSTZRANGE(lower(requests.when) - INTERVAL '1 HOUR', upper(requests.when) + INTERVAL '1 HOUR', '()') && 
         TSTZRANGE(lower(announcements.when)), upper(announcements.when), '()') AND
         requests.user_id = 42
  ) = 0
)

Answer 1

查看文档的“高级Postgres支持”部分，http://api.rom-rb.org/rom-sql/ROM/SQL/Postgres/Types看起来像是对TsTzRange range('tstzrange', range_read_type(:tstzrange))的支持

Answer 2

我找到了解决问题的方法。不确定rom-sql中是否正确。如果有的话，我会接受更好的答案。

在此之前，这是我的解决方案-Sequel.lit 在我的情况下，我在“公告”关系中定义了一个方法：

  def available(user_id)
    request_ids = requests.by_user_id(user_id).confirmed.pluck(:id)

    # +- 1 hour around request is not available
    # last argument '()' means "do not include boundaries"
    request_when = "TSTZRANGE(
      lower(requests.when) - INTERVAL '1 HOUR',
      upper(requests.when) + INTERVAL '1 HOUR',
      '()'
    )"

    announcement_when = "TSTZRANGE(lower(announcements.when), upper(announcements.when), '()')"

    where(Sequel.lit(
      "(SELECT COUNT(requests.id)
      FROM requests
      WHERE requests.id IN (:request_ids) AND
            #{request_when} && #{announcement_when} AND
            requests.user_id = :user_id) = 0",
      user_id: user_id, request_ids: request_ids
    ))
  end

如何在rom-sql中构造TSTZRANGE？

2 个答案: