Ruby on rails 列出与当前activerecord对象不相关的数据

你可以把它写在一行里

group = Group.find(id) // lets say group 1
// find tests that are not added to this group 

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首先找到属于特定组的测试ID，然后使用或也可以使用@Vasilisa查询使用连接

Test.left_outer_joins(:groups).where.not(groups: {id: id})

一班轮

group_test_ids = group.tests.ids #test ids which belongs to group

tests = Test.where.not(id: group_test_ids) # tests which not contain that group

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试试这个

group\u test\u ids=group.tests.ids

tests=test.where.not（id:group\u test\u ids）

@ts good one:）。我想我不应该给表命名

group

。它与内置的活动记录冲突method@ts我把它修好后，让我试试你的解决办法，但我肯定会的

group_test_ids = group.tests.ids #test ids which belongs to group

tests = Test.where.not(id: group_test_ids) # tests which not contain that group

tests = Test.where.not(id: group.tests.ids)