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+# Iterating Tables In Batches
+
+Rails provides a method called `in_batches` that can be used to iterate over
+rows in batches. For example:
+
+```ruby
+User.in_batches(of: 10) do |relation|
+  relation.update_all(updated_at: Time.now)
+end
+```
+
+Unfortunately this method is implemented in a way that is not very efficient,
+both query and memory usage wise.
+
+To work around this you can include the `EachBatch` module into your models,
+then use the `each_batch` class method. For example:
+
+```ruby
+class User < ActiveRecord::Base
+  include EachBatch
+end
+
+User.each_batch(of: 10) do |relation|
+  relation.update_all(updated_at: Time.now)
+end
+```
+
+This will end up producing queries such as:
+
+```
+User Load (0.7ms)  SELECT  "users"."id" FROM "users" WHERE ("users"."id" >= 41654)  ORDER BY "users"."id" ASC LIMIT 1 OFFSET 1000
+  (0.7ms)  SELECT COUNT(*) FROM "users" WHERE ("users"."id" >= 41654) AND ("users"."id" < 42687)
+```
+
+The API of this method is similar to `in_batches`, though it doesn't support
+all of the arguments that `in_batches` supports. You should always use
+`each_batch` _unless_ you have a specific need for `in_batches`.