java - 从 ResultSet 中获取行数

Question

我正在尝试获取我从查询中获取的 ResultSet 中的数字，如下面的代码所示。查询检索数字 5。如何从 ResultSet 中获取此数字？

代码:

String sql_count_stop = "select count(*) FROM behaviour where  mac = ? ";
PreparedStatement preparedCount = con.prepareStatement(sql_count_stop);
preparedCount.setString(1, macD);
ResultSet rsCount = preparedCount.executeQuery();
while(rsCount.next()){

}

Answer 1

您可以将查询修改为

"SELECT count(*) AS totalCount FROM behaviour WHERE mac = ? ";

然后使用，

macId= rsCount.getInt("totalCount");