Module: CompositePrimaryKeys::ActiveRecord::AssociationPreload::ClassMethods

Defined in:
lib/composite_primary_keys/association_preload.rb

Overview

Composite key versions of Association functions

Instance Method Summary collapse

Instance Method Details

#find_associated_records(ids, reflection, preload_options) ⇒ Object 



116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
 
# File 'lib/composite_primary_keys/association_preload.rb', line 116

def find_associated_records(ids, reflection, preload_options)
  options = reflection.options
  table_name = reflection.klass.quoted_table_name

  if interface = reflection.options[:as]
    conditions = "#{reflection.klass.quoted_table_name}.#{connection.quote_column_name "#{interface}_id"} #{in_or_equals_for_ids(ids)} and #{reflection.klass.quoted_table_name}.#{connection.quote_column_name "#{interface}_type"} = '#{self.base_class.sti_name}'"
  else
    foreign_key = reflection.cpk_primary_key

    where = (foreign_key * ids.size).in_groups_of(foreign_key.size).map do |keys|
      "(" + keys.map{|key| "#{reflection.klass.quoted_table_name}.#{connection.quote_column_name(key)} = ?"}.join(" AND ") + ")"
    end.join(" OR ")

    conditions = [where, ids].flatten
  end

  conditions[0] << append_conditions(reflection, preload_options)

  find_options = {
    :select => preload_options[:select] || options[:select] || "#{table_name}.*",
    :include => preload_options[:include] || options[:include],
    # CPK
    # :conditions => [conditions, ids],
    :conditions => conditions,
    :joins => options[:joins],
    :group => preload_options[:group] || options[:group],
    :order => preload_options[:order] || options[:order]
  }

  reflection.klass.unscoped.apply_finder_options(find_options).to_a
end

#full_composite_join_clause(reflection, table1, full_keys1, table2, full_keys2) ⇒ Object 



148
149
150
151
152
153
154
155
156
157
158
 
# File 'lib/composite_primary_keys/association_preload.rb', line 148

def full_composite_join_clause(reflection, table1, full_keys1, table2, full_keys2)
  connection = reflection.active_record.connection
  full_keys1 = full_keys1.split(CompositePrimaryKeys::ID_SEP) if full_keys1.is_a?(String)
  full_keys2 = full_keys2.split(CompositePrimaryKeys::ID_SEP) if full_keys2.is_a?(String)
  where_clause = [full_keys1, full_keys2].transpose.map do |key_pair|
    quoted1 = connection.quote_table_name(table1)
    quoted2 = connection.quote_table_name(table2)
    "#{quoted1}.#{connection.quote_column_name(key_pair.first)}=#{quoted2}.#{connection.quote_column_name(key_pair.last)}"
  end.join(" AND ")
  "(#{where_clause})"
end

#preload_belongs_to_association(records, reflection, preload_options = {}) ⇒ Object 



48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
 
# File 'lib/composite_primary_keys/association_preload.rb', line 48

def preload_belongs_to_association(records, reflection, preload_options={})
  return if records.first.send("loaded_#{reflection.name}?")
  options = reflection.options
  
  ids = Array.new
  
  if options[:polymorphic]
    # CPK
    #polymorph_type = options[:foreign_type]
    #klasses_and_ids = {}

    # Construct a mapping from klass to a list of ids to load and a mapping of those ids back to their parent_records
    #records.each do |record|
    #  if klass = record.send(polymorph_type)
    #    klass_id = record.send(primary_key_name)
    #    if klass_id
    #      id_map = klasses_and_ids[klass] ||= {}
    #      id_list_for_klass_id = (id_map[klass_id.to_s] ||= [])
    #      id_list_for_klass_id << record
    #    end
    #  end
    #end
    #klasses_and_ids = klasses_and_ids.to_a
    raise AssociationNotSupported, "Polymorphic joins not supported for composite keys"
  else
    # I need to keep the original ids for each record (as opposed to the stringified) so
    # that they get properly converted for each db so the id_map ends up looking like:
    #
    # { '1,2' => {:id => [1,2], :records => [...records...]}}
    id_map = {}

    records.each do |record|
      keys = reflection.cpk_primary_key.map{|k| record.send(k)}
      ids << keys

      mapped_records = (id_map[keys.to_s] ||= [])
      mapped_records << record
    end

    klasses_and_ids = [[reflection.klass.name, id_map]]
  end

  klasses_and_ids.each do |klass_and_id|
    klass_name, id_map = *klass_and_id
    next if id_map.empty?
    klass = klass_name.constantize

    table_name = klass.quoted_table_name
    primary_key = [reflection.options[:primary_key] || klass.primary_key].flatten

    # CPK
    conditions = id_map.map do |key, value|
      "(" +
      primary_key.map do |key|
        "#{table_name}.#{connection.quote_column_name(key)} = ?"
      end.join(' AND ') + ")"
    end.join(' OR ')

    conditions << append_conditions(reflection, preload_options)

    conditions = [conditions] + ids.uniq.flatten

    associated_records = klass.unscoped.where(conditions).apply_finder_options(options.slice(:include, :select, :joins, :order)).to_a

    set_association_single_records(id_map, reflection.name, associated_records, primary_key)
  end
end

#preload_has_and_belongs_to_many_association(records, reflection, preload_options = {}) ⇒ Object 



11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
 
# File 'lib/composite_primary_keys/association_preload.rb', line 11

def preload_has_and_belongs_to_many_association(records, reflection, preload_options={})
  table_name = reflection.klass.quoted_table_name
  id_to_record_map, ids = construct_id_map(records)
  records.each {|record| record.send(reflection.name).loaded}
  options = reflection.options

  if composite?
    where = (primary_key * ids.size).in_groups_of(primary_key.size).map do |keys|
      "(" + keys.map{|key| "t0.#{connection.quote_column_name(key)} = ?"}.join(" AND ") + ")"
    end.join(" OR ")

    conditions = [where, ids].flatten
    joins = "INNER JOIN #{connection.quote_table_name options[:join_table]} t0 ON #{full_composite_join_clause(reflection, reflection.klass.table_name, reflection.klass.primary_key, 't0', reflection.association_foreign_key)}"
    parent_primary_keys = reflection.cpk_primary_key.map{|k| "t0.#{connection.quote_column_name(k)}"}

    concat_arr = ["'['"] +
                 parent_primary_keys.zip(["', '"] * (parent_primary_keys.size - 1)).flatten.compact +
                 ["']'"]

    parent_record_id = connection.concat(*concat_arr)
  else
    conditions = "t0.#{reflection.primary_key_name} #{in_or_equals_for_ids(ids)}"
    conditions << append_conditions(reflection, preload_options)
    conditions = [conditions, ids]
    joins = "INNER JOIN #{connection.quote_table_name options[:join_table]} t0 ON #{reflection.klass.quoted_table_name}.#{reflection.klass.primary_key} = t0.#{reflection.association_foreign_key}"
    parent_record_id = reflection.primary_key_name
 end

associated_records = reflection.klass.unscoped.where(conditions).
    includes(options[:include]).
    joins(joins).
    select("#{options[:select] || table_name+'.*'}, #{parent_record_id} as the_parent_record_id").
    order(options[:order]).to_a

  set_association_collection_records(id_to_record_map, reflection.name, associated_records, 'the_parent_record_id')
end