dbGetRowsAffected() returns a scalar number (integer or numeric), the number of rows affected by a data manipulation statement issued with dbSendStatement(). The value is available directly after the call and does not change after calling dbFetch(). For queries issued with dbSendQuery(), zero is returned before and after the call to dbFetch(). Attempting to get the rows affected for a result set cleared with dbClearResult() gives an error.