module Neo4j::Core::QueryFindInBatches

Public Instance Methods

find_each(*args, &block) click to toggle source
   # File lib/neo4j/core/query_find_in_batches.rb
27 def find_each(*args, &block)
28   find_in_batches(*args) { |batch| batch.each(&block) }
29 end
find_in_batches(node_var, prop_var, options = {}) { |records| ... } click to toggle source
   # File lib/neo4j/core/query_find_in_batches.rb
 4 def find_in_batches(node_var, prop_var, options = {})
 5   validate_find_in_batches_options!(options)
 6 
 7   batch_size = options.delete(:batch_size) || 1000
 8 
 9   query = reorder(node_var => prop_var).limit(batch_size)
10 
11   records = query.to_a
12 
13   while records.any?
14     records_size = records.size
15     primary_key_offset = primary_key_offset(records.last, node_var, prop_var)
16 
17     yield records
18 
19     break if records_size < batch_size
20 
21     primary_key_var = Neo4j::Core::QueryClauses::Clause.from_key_and_single_value(node_var, prop_var)
22     records = query.where("#{primary_key_var} > {primary_key_offset}")
23                    .params(primary_key_offset: primary_key_offset).to_a
24   end
25 end

Private Instance Methods

primary_key_offset(last_record, node_var, prop_var) click to toggle source
   # File lib/neo4j/core/query_find_in_batches.rb
38 def primary_key_offset(last_record, node_var, prop_var)
39   last_record.send(node_var).send(prop_var)
40 rescue NoMethodError
41   begin
42     last_record.send(node_var).properties[prop_var.to_sym]
43   rescue NoMethodError
44     last_record.send("#{node_var}.#{prop_var}") # In case we're explicitly returning it
45   end
46 end
validate_find_in_batches_options!(options) click to toggle source
   # File lib/neo4j/core/query_find_in_batches.rb
33 def validate_find_in_batches_options!(options)
34   invalid_keys = options.keys.map(&:to_sym) - [:batch_size]
35   fail ArgumentError, "Invalid keys: #{invalid_keys.join(', ')}" if not invalid_keys.empty?
36 end