| Class | AWS::Record::HashModel::Scope |
| In: |
lib/aws/record/hash_model/scope.rb
|
| Parent: | Record::Scope |
The primary interface for finding records with {AWS::Record::HashModel}.
You should normally never need to construct a Scope object directly. Scope objects are returned from the AWS::Record::HashModel finder methods # (e.g. shard and limit).
books = Book.limit(100) books.class #=> AWS::Record::HashModel::Scope
Scopes are also returned from methods defined with the scope method.
class Book < AWS::Record::HashModel
scope :sampling, limit(10)
end
Book.sampling #=> returns a scope that limits to 10
Scope objects represent a request, but do not actualy make a request until required. This allows you to chain requests
# no request made by the following 2 statements
books = Book.shard('books-1') # what table to search
books = books.limit(10) # how many records to fetch
books.each do |book|
# yields up to 10 books from the table 'books-1'
end
The following methods returns a scope that can be chained.
To terminate a scope you can enumerate it or call first.
# terminate a scope by enumerating
Book.limit(10).each {|book| ... }
# terminate a scope by getting the first record
Book.shard('books-1').first