# File lib/active_record/connection_adapters/abstract_mysql_adapter.rb, line 576 def quoted_columns_for_index(column_names, options = {}) option_strings = Hash[column_names.map {|name| [name, '']}] # add index length option_strings = add_index_length(option_strings, column_names, options) # add index sort order option_strings = add_index_sort_order(option_strings, column_names, options) column_names.map {|name| quote_column_name(name) + option_strings[name]} end