# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 326
      def add(pool, table_name)
        pool.with_connection do
          if data_source_exists?(pool, table_name)
            primary_keys(pool, table_name)
            columns(pool, table_name)
            columns_hash(pool, table_name)
            indexes(pool, table_name)
          end
        end
      end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 294
      def cached?(table_name)
        @columns.key?(table_name)
      end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 388
      def clear_data_source_cache!(_connection, name)
        @columns.delete name
        @columns_hash.delete name
        @primary_keys.delete name
        @data_sources.delete name
        @indexes.delete name
      end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 338
      def columns(pool, table_name)
        if ignored_table?(table_name)
          raise ActiveRecord::StatementInvalid.new("Table '#{table_name}' doesn't exist", connection_pool: pool)
        end

        @columns.fetch(table_name) do
          pool.with_connection do |connection|
            @columns[deep_deduplicate(table_name)] = deep_deduplicate(connection.columns(table_name))
          end
        end
      end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 352
      def columns_hash(pool, table_name)
        @columns_hash.fetch(table_name) do
          @columns_hash[deep_deduplicate(table_name)] = columns(pool, table_name).index_by(&:name).freeze
        end
      end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 359
      def columns_hash?(_pool, table_name)
        @columns_hash.key?(table_name)
      end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 309
      def data_source_exists?(pool, name)
        return if ignored_table?(name)

        if @data_sources.empty?
          tables_to_cache(pool).each do |source|
            @data_sources[source] = true
          end
        end

        return @data_sources[name] if @data_sources.key? name

        @data_sources[deep_deduplicate(name)] = pool.with_connection do |connection|
          connection.data_source_exists?(name)
        end
      end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 406
      def dump_to(filename)
        open(filename) { |f|
          if filename.include?(".dump")
            f.write(Marshal.dump(self))
          else
            f.write(YAML.dump(self))
          end
        }
      end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 363
      def indexes(pool, table_name)
        @indexes.fetch(table_name) do
          pool.with_connection do |connection|
            if data_source_exists?(pool, table_name)
              @indexes[deep_deduplicate(table_name)] = deep_deduplicate(connection.indexes(table_name))
            else
              []
            end
          end
        end
      end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 298
      def primary_keys(pool, table_name)
        @primary_keys.fetch(table_name) do
          pool.with_connection do |connection|
            if data_source_exists?(pool, table_name)
              @primary_keys[deep_deduplicate(table_name)] = deep_deduplicate(connection.primary_key(table_name))
            end
          end
        end
      end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 379
      def schema_version
        @version
      end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 383
      def size
        [@columns, @columns_hash, @primary_keys, @data_sources].sum(&:size)
      end

# File activerecord/lib/active_record/connection_adapters/schema_cache.rb, line 375
      def version(pool)
        @version ||= pool.with_connection(&:schema_version)
      end