diff options
Diffstat (limited to 'activerecord/lib/active_record/relation/batches.rb')
| -rw-r--r-- | activerecord/lib/active_record/relation/batches.rb | 58 |
1 files changed, 39 insertions, 19 deletions
diff --git a/activerecord/lib/active_record/relation/batches.rb b/activerecord/lib/active_record/relation/batches.rb index b921f2eddb..41291844fc 100644 --- a/activerecord/lib/active_record/relation/batches.rb +++ b/activerecord/lib/active_record/relation/batches.rb @@ -11,7 +11,7 @@ module ActiveRecord # The #find_each method uses #find_in_batches with a batch size of 1000 (or as # specified by the +:batch_size+ option). # - # Person.all.find_each do |person| + # Person.find_each do |person| # person.do_awesome_stuff # end # @@ -19,8 +19,26 @@ module ActiveRecord # person.party_all_night! # end # - # You can also pass the +:start+ option to specify - # an offset to control the starting point. + # ==== Options + # * <tt>:batch_size</tt> - Specifies the size of the batch. Default to 1000. + # * <tt>:start</tt> - Specifies the starting point for the batch processing. + # 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). + # + # # Let's process for a batch of 2000 records, skiping the first 2000 rows + # Person.find_each(start: 2000, batch_size: 2000) do |person| + # person.party_all_night! + # end + # + # NOTE: 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 means that this method only works with integer-based + # primary keys. + # + # NOTE: You can't set the limit either, that's used to control + # the batch sizes. def find_each(options = {}) find_in_batches(options) do |records| records.each { |record| yield record } @@ -28,31 +46,33 @@ module ActiveRecord 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. - # - # 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). - # - # 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 means that this method only works with integer-based - # primary keys. You can't set the limit either, that's used to control - # the batch sizes. + # an array. # # Person.where("age > 21").find_in_batches do |group| # sleep(50) # Make sure it doesn't get too crowded in there! # group.each { |person| person.party_all_night! } # end # + # ==== Options + # * <tt>:batch_size</tt> - Specifies the size of the batch. Default to 1000. + # * <tt>:start</tt> - Specifies the starting point for the batch processing. + # 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). + # # # Let's process the next 2000 records - # Person.all.find_in_batches(start: 2000, batch_size: 2000) do |group| + # Person.find_in_batches(start: 2000, batch_size: 2000) do |group| # group.each { |person| person.party_all_night! } # end + # + # NOTE: 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 means that this method only works with integer-based + # primary keys. + # + # NOTE: You can't set the limit either, that's used to control + # the batch sizes. def find_in_batches(options = {}) options.assert_valid_keys(:start, :batch_size) |