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34 lines
856 B
Markdown
34 lines
856 B
Markdown
# Get An Empty ActiveRecord Relation
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When you query for something (with `#where`) and there are no results matching
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that query, you get something that looks like an empty array (`[]`), but it's
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not quite.
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```ruby
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> result
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[]
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> result.class
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Book::ActiveRecord_Relation
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```
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It's an empty [`ActiveRecord`
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relation](https://api.rubyonrails.org/classes/ActiveRecord/Relation.html).
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You can get an instance of an empty `ActiveRecord` relation without
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constructing a _no result_ query.
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```ruby
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> Book.none
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[]
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> Book.none.class
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Book::ActiveRecord_Relation
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```
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I can think of a couple scenarios where this would be useful:
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- as a default value for a method parameter
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- as a test value for a method that expects to have an `ActiveRecord` relation
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passed in
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[source](https://stackoverflow.com/questions/4877931/how-to-return-an-empty-activerecord-relation)
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