active? (ActiveRecord::ConnectionAdapters::PostgreSQLAdapter)

    # File lib/active_record/connection_adapters/postgresql_adapter.rb, line 255
          def active?
            if @connection.respond_to?(:status)
              @connection.status == PGconn::CONNECTION_OK
            else
              # We're asking the driver, not ActiveRecord, so use @connection.query instead of #query
              @connection.query 'SELECT 1'
              true
            end
          # postgres-pr raises a NoMethodError when querying if no connection is available.
          rescue PGError, NoMethodError
            false
          end