module ScopedSearch::QueryBuilder::Field

This module gets included into the Field class to add SQL generation.

Public Instance Methods

construct_join_sql(key_relation, num) click to toggle source

This method construct join statement for a key value table It assume the following table structure

+----------+  +---------+ +--------+
| main     |  | value   | | key    |
| main_pk  |  | main_fk | |        |
|          |  | key_fk  | | key_pk |
+----------+  +---------+ +--------+

uniq name for the joins are needed in case that there is more than one condition on different keys in the same query.

# File lib/scoped_search/query_builder.rb, line 330
def construct_join_sql(key_relation, num)
  join_sql = ""
  connection = klass.connection
  key = key_relation.to_s.singularize.to_sym

  key_table = definition.reflection_by_name(klass, key).table_name
  value_table = klass.table_name.to_s

  value_table_fk_key, key_table_pk = reflection_keys(definition.reflection_by_name(klass, key))

  main_reflection = definition.reflection_by_name(definition.klass, relation)
  if main_reflection
    main_table = definition.klass.table_name
    main_table_pk, value_table_fk_main = reflection_keys(definition.reflection_by_name(definition.klass, relation))

    join_sql = "\n  INNER JOIN #{connection.quote_table_name(value_table)} #{value_table}_#{num} ON (#{main_table}.#{main_table_pk} = #{value_table}_#{num}.#{value_table_fk_main})"
    value_table = " #{value_table}_#{num}"
  end
  join_sql += "\n INNER JOIN #{connection.quote_table_name(key_table)} #{key_table}_#{num} ON (#{key_table}_#{num}.#{key_table_pk} = #{value_table}.#{value_table_fk_key}) "

  return join_sql
end
construct_simple_join_sql(num) click to toggle source

This method construct join statement for a key value table It assume the following table structure

+----------+  +---------+
| main     |  | key     |
| main_pk  |  | value   |
|          |  | main_fk |
+----------+  +---------+

uniq name for the joins are needed in case that there is more than one condition on different keys in the same query.

# File lib/scoped_search/query_builder.rb, line 362
def construct_simple_join_sql(num)
  connection = klass.connection
  key_value_table = klass.table_name

  main_table = definition.klass.table_name
  main_table_pk, value_table_fk_main = reflection_keys(definition.reflection_by_name(definition.klass, relation))

  join_sql = "\n  INNER JOIN #{connection.quote_table_name(key_value_table)} #{key_value_table}_#{num} ON (#{connection.quote_table_name(main_table)}.#{connection.quote_column_name(main_table_pk)} = #{key_value_table}_#{num}.#{connection.quote_column_name(value_table_fk_main)})"
  return join_sql
end
reflection_conditions(reflection) click to toggle source
# File lib/scoped_search/query_builder.rb, line 381
def reflection_conditions(reflection)
  return unless reflection
  conditions = reflection.options[:conditions]
  conditions ||= "#{reflection.options[:source]}_type = '#{reflection.options[:source_type]}'" if reflection.options[:source] && reflection.options[:source_type]
  conditions ||= "#{reflection.try(:foreign_type)} = '#{reflection.klass}'" if  reflection.options[:polymorphic]
  " AND #{conditions}" if conditions
end
reflection_keys(reflection) click to toggle source
# File lib/scoped_search/query_builder.rb, line 373
def reflection_keys(reflection)
  pk = reflection.klass.primary_key
  fk = reflection.options[:foreign_key]
  # activerecord prior to 3.1 doesn't respond to foreign_key method and hold the key name in the reflection primary key
  fk ||= reflection.respond_to?(:foreign_key) ? reflection.foreign_key : reflection.primary_key_name
  reflection.macro == :belongs_to ? [fk, pk] : [pk, fk]
end
to_ext_method_sql(key, operator, value) { |:include, content| ... } click to toggle source
# File lib/scoped_search/query_builder.rb, line 389
def to_ext_method_sql(key, operator, value, &block)
  raise ScopedSearch::QueryNotSupported, "'#{definition.klass}' doesn't respond to '#{ext_method}'" unless definition.klass.respond_to?(ext_method)
  conditions = definition.klass.send(ext_method.to_sym,key, operator, value) rescue {}
  raise ScopedSearch::QueryNotSupported, "external method '#{ext_method}' should return hash" unless conditions.kind_of?(Hash)
  sql = ''
  conditions.map do |notification, content|
    case notification
      when :include then yield(:include, content)
      when :joins then yield(:joins, content)
      when :conditions then sql = content
      when :parameter then content.map{|c| yield(:parameter, c)}
    end
  end
  return sql
end
to_sql(operator = nil) { |finder_option_type, value| ... } click to toggle source

Return an SQL representation for this field. Also make sure that the relation which includes the search field is included in the SQL query.

This function may yield an :include that should be used in the ActiveRecord::Base#find call, to make sure that the field is available for the SQL query.

# File lib/scoped_search/query_builder.rb, line 300
def to_sql(operator = nil, &block) # :yields: finder_option_type, value
  num = rand(1000000)
  connection = klass.connection
  if key_relation
    yield(:joins, construct_join_sql(key_relation, num) )
    yield(:keycondition, "#{key_klass.table_name}_#{num}.#{connection.quote_column_name(key_field.to_s)} = ?")
    klass_table_name = relation ? "#{klass.table_name}_#{num}" : klass.table_name
    return "#{connection.quote_table_name(klass_table_name)}.#{connection.quote_column_name(field.to_s)}"
  elsif key_field
    yield(:joins, construct_simple_join_sql(num))
    yield(:keycondition, "#{key_klass.table_name}_#{num}.#{connection.quote_column_name(key_field.to_s)} = ?")
    klass_table_name = relation ? "#{klass.table_name}_#{num}" : klass.table_name
    return "#{connection.quote_table_name(klass_table_name)}.#{connection.quote_column_name(field.to_s)}"
  elsif relation
    yield(:include, relation)
  end
  column_name = connection.quote_table_name(klass.table_name.to_s) + "." + connection.quote_column_name(field.to_s)
  column_name = "(#{column_name} >> #{offset*word_size} & #{2**word_size - 1})" if offset
  column_name
end