diff options
Diffstat (limited to 'activerecord/lib/active_record/batches.rb')
| -rw-r--r-- | activerecord/lib/active_record/batches.rb | 38 |
1 files changed, 23 insertions, 15 deletions
diff --git a/activerecord/lib/active_record/batches.rb b/activerecord/lib/active_record/batches.rb index 03bd4f9f93..5a6cecd4ad 100644 --- a/activerecord/lib/active_record/batches.rb +++ b/activerecord/lib/active_record/batches.rb @@ -4,10 +4,12 @@ module ActiveRecord base.extend(ClassMethods) end - # When processing large numbers of records, it's often a good idea to do so in batches to prevent memory ballooning. + # When processing large numbers of records, it's often a good idea to do + # so in batches to prevent memory ballooning. module ClassMethods - # Yields each record that was found by the find +options+. The find is performed by find_in_batches - # with a batch size of 1000 (or as specified by the +batch_size+ option). + # Yields each record that was found by the find +options+. The find is + # performed by find_in_batches with a batch size of 1000 (or as + # specified by the <tt>:batch_size</tt> option). # # Example: # @@ -15,9 +17,10 @@ module ActiveRecord # person.party_all_night! # end # - # Note: This method is only intended to use for batch processing of large amounts of records that wouldn't fit in - # memory all at once. If you just need to loop over less than 1000 records, it's probably better just to use the - # regular find methods. + # Note: This method is only intended to use for batch processing of + # large amounts of records that wouldn't fit in memory all at once. If + # you just need to loop over less than 1000 records, it's probably + # better just to use the regular find methods. def find_each(options = {}) find_in_batches(options) do |records| records.each { |record| yield record } @@ -26,17 +29,22 @@ module ActiveRecord self end - # Yields each batch of records that was found by the find +options+ as an array. The size of each batch is - # set by the +batch_size+ option; the default is 1000. + # Yields each batch of records that was found by the find +options+ as + # an array. The size of each batch is set by the <tt>:batch_size</tt> + # option; the default is 1000. # - # You can control the starting point for the batch processing by supplying the +start+ option. This is especially - # useful if you want multiple workers dealing with the same processing queue. You can make worker 1 handle all the - # records between id 0 and 10,000 and worker 2 handle from 10,000 and beyond (by setting the +start+ option on that - # worker). + # You can control the starting point for the batch processing by + # supplying the <tt>:start</tt> option. This is especially useful if you + # want multiple workers dealing with the same processing queue. You can + # make worker 1 handle all the records between id 0 and 10,000 and + # worker 2 handle from 10,000 and beyond (by setting the <tt>:start</tt> + # option on that worker). # - # It's not possible to set the order. That is automatically set to ascending on the primary key ("id ASC") - # to make the batch ordering work. This also mean that this method only works with integer-based primary keys. - # You can't set the limit either, that's used to control the the batch sizes. + # It's not possible to set the order. That is automatically set to + # ascending on the primary key ("id ASC") to make the batch ordering + # work. This also mean that this method only works with integer-based + # primary keys. You can't set the limit either, that's used to control + # the the batch sizes. # # Example: # |