检查attr数组是否包含Rails中给定数组的任何元素 [英] Check if attr array contains any of element from given array in Rails

问题描述

我有一个项目Obj列表：

I have a list of items Obj:

obj1.val = ["foo"]
obj2.val = ["bar"]
obj3.val = ["bar", "foo"]

我有一个数组 check_list = [ foo， bar]

我知道像 Obj.where（'val @> ARRAY [？]'，check_list）这样的代码将返回 obj3 ，因为它包含 foo和 bar，但我想创建一个将返回所有项目的函数。

I know that code like Obj.where('val @> ARRAY[?]', check_list) will return obj3 because it contains "foo" and "bar" but I want to create a function that will return all items.

我在考虑类似这样的循环：基于 check_list.each ，但看起来并不好。

I was thinking about some loop like: based on check_list.each but it just doesn't look good. How to make such a query?

推荐答案

请使用 && 重叠运算符。

Please use the && overlap operator.

Obj.where('val && ARRAY[?]', check_list)

试用示例：

development=# select id, group_ids from users;
 id | group_ids
----+-----------
  1 | {1}
  2 | {1,2}
  3 | {2}
(3 rows)

[arup@sampl_admin (master)]$ rails c
Loading development environment (Rails 4.2.3)
>> User.where('group_ids && ARRAY[?]', [1, 2]).pluck(:id, :group_ids)
   (1.0ms)  SELECT "users"."id", "users"."group_ids" FROM "users" WHERE (group_ids && ARRAY[1,2])
# => [[1, [1]], [2, [1, 2]], [3, [2]]]

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