initialize_dup

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 19
      def initialize_dup(other)
        super
        @columns      = @columns.dup
        @columns_hash = @columns_hash.dup
        @primary_keys = @primary_keys.dup
        @data_sources = @data_sources.dup
        @indexes      = @indexes.dup
      end