133c21b801
Update to Rails 2.3.1.
(Actually, not quite. Doesn't look like 2.3.1 will be released
today, but I REALLY want to push these bugfixes out.)
Removed bundled Rack (Rails 2.3.1 comes bundled with Rack 1.0).
Add
config.action_view.cache_template_loading = true
to production environment.
Fix FastCGI bug (http://rubyforge.org/tracker/index.php?func=detail&aid=24191&group_id=186&atid=783).
Fix WikiWords bug (http://rubyforge.org/pipermail/instiki-users/2009-February/001181.html).
70 lines
2.9 KiB
Ruby
70 lines
2.9 KiB
Ruby
module ActiveRecord
|
|
module Batches # :nodoc:
|
|
def self.included(base)
|
|
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.
|
|
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).
|
|
#
|
|
# Example:
|
|
#
|
|
# Person.each(:conditions => "age > 21") do |person|
|
|
# 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.
|
|
def each(options = {})
|
|
find_in_batches(options) do |records|
|
|
records.each { |record| yield record }
|
|
end
|
|
|
|
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.
|
|
#
|
|
# 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 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:
|
|
#
|
|
# Person.find_in_batches(:conditions => "age > 21") do |group|
|
|
# sleep(50) # Make sure it doesn't get too crowded in there!
|
|
# group.each { |person| person.party_all_night! }
|
|
# end
|
|
def find_in_batches(options = {})
|
|
raise "You can't specify an order, it's forced to be #{batch_order}" if options[:order]
|
|
raise "You can't specify a limit, it's forced to be the batch_size" if options[:limit]
|
|
|
|
start = options.delete(:start).to_i
|
|
|
|
with_scope(:find => options.merge(:order => batch_order, :limit => options.delete(:batch_size) || 1000)) do
|
|
records = find(:all, :conditions => [ "#{table_name}.#{primary_key} >= ?", start ])
|
|
|
|
while records.any?
|
|
yield records
|
|
records = find(:all, :conditions => [ "#{table_name}.#{primary_key} > ?", records.last.id ])
|
|
end
|
|
end
|
|
end
|
|
|
|
|
|
private
|
|
def batch_order
|
|
"#{table_name}.#{primary_key} ASC"
|
|
end
|
|
end
|
|
end
|
|
end |