Module: ScopedSearch::QueryBuilder::Field

Defined in:
lib/scoped_search/query_builder.rb

Overview

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

Instance Method Summary collapse

Instance Method Details

#construct_join_sql(key_relation, num) ⇒ Object

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.


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# File 'lib/scoped_search/query_builder.rb', line 354

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) ⇒ Object

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.


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# File 'lib/scoped_search/query_builder.rb', line 386

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) ⇒ Object


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# File 'lib/scoped_search/query_builder.rb', line 405

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) ⇒ Object


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# File 'lib/scoped_search/query_builder.rb', line 397

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, &block) ⇒ Object


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# File 'lib/scoped_search/query_builder.rb', line 413

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)
  begin
    conditions = definition.klass.send(ext_method.to_sym, key, operator, value)
  rescue StandardError => e
    raise ScopedSearch::QueryNotSupported, "external method '#{ext_method}' failed with error: #{e}"
  end
  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, &block) ⇒ Object

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.


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# File 'lib/scoped_search/query_builder.rb', line 324

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