【发布时间】：2017-01-26 16:29:30
【问题描述】：
我的网球日历模型将周属性设置为数组数据类型，因为锦标赛可以持续两周。例如，第一个元素如下：
2.3.1 :001 > AtpCalendar.first
AtpCalendar Load (0.8ms) SELECT "atp_calendars".* FROM "atp_calendars" ORDER BY "atp_calendars"."id" ASC LIMIT $1 [["LIMIT", 1]]
=> #<AtpCalendar id: 1, name: "Brisbane", category: "ATP 250", week: [1], created_at: "2017-01-25 17:29:36", updated_at: "2017-01-25 17:29:36">
如果我向 Postgresql 查询星期属性的类型，我会得到预期的答案：
2.3.1 :001 > AtpCalendar.first.week == [1]
AtpCalendar Load (0.8ms) SELECT "atp_calendars".* FROM "atp_calendars" ORDER BY "atp_calendars"."id" ASC LIMIT $1 [["LIMIT", 1]]
=> true
2.3.1 :001 > AtpCalendar.first.week.class
AtpCalendar Load (0.9ms) SELECT "atp_calendars".* FROM "atp_calendars" ORDER BY "atp_calendars"."id" ASC LIMIT $1 [["LIMIT", 1]]
=> Array
所以到目前为止没有问题。
但是，如果我在 Postgres 中查询特定周值，例如 [1]，我会收到错误消息：
2.3.1 :002 > AtpCalendar.where('week = ?', [1])
AtpCalendar Load (1.7ms) SELECT "atp_calendars".* FROM "atp_calendars" WHERE (week = 1)
ActiveRecord::StatementInvalid: PG::UndefinedFunction: ERROR: operator does not exist: integer[] = integer
LINE 1: ...LECT "atp_calendars".* FROM "atp_calendars" WHERE (week = 1)
^
HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts.
我也尝试了不同的查询，但结果是一样的：
2.3.1 :001 > AtpCalendar.where("week @> ?", 1)
AtpCalendar Load (1.6ms) SELECT "atp_calendars".* FROM "atp_calendars" WHERE (week @> 1)
ActiveRecord::StatementInvalid: PG::UndefinedFunction: ERROR: operator does not exist: integer[] @> integer
LINE 1: ...ECT "atp_calendars".* FROM "atp_calendars" WHERE (week @> 1)
^
HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts.
我可能遗漏了一些东西，但我不明白是什么。
当我使用查询AtpCalendar.find_by(week: [1])时出现同样的错误
【问题讨论】：
标签： ruby-on-rails postgresql rails-activerecord