我对MySQL很陌生,我想知道:转储mysql数据库时只需几秒钟,但加载它时有时需要几分钟!在几秒钟内加载数据库有没有相反的mysqldump?
我试图通过引入开始和结束日期来绘制使用时间序列的条形图,但是我指出了它指示的结束日期的问题:线程"main"中的异常org.jfree.data.general.SeriesException:您正在尝试添加时间段的观察4 -mai-2011但该系列已包含该时段的观察结果.不允许重复.尝试使用该addOrUpdate()方法.
final TimeSeries series2 = new TimeSeries("ip max", Day.class);
String datebegin = "04/29/2011 02:00:01";
String dateend = "05/04/2011 02:00:01";
DateFormat formatter;
Date date;
formatter = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss");
date = formatter.parse(datebegin);
Calendar cal1 = Calendar.getInstance();
cal1.setTime(date);
Date date2;
date2 = (Date) formatter.parse(dateend);
Calendar cal2 = Calendar.getInstance();
cal2.setTime(date2);
while (((cal1.compareTo(cal2)) != 0)) {
cal1.add(Calendar.HOUR, 24);
String intermediatestringdate = formatter.format(cal1.getTime());
System.out.println( intermediatestringdate);
Date intermediatedate = (Date) formatter.parse(dateend);
series2.add(new Day(intermediatedate),500);
}
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