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摘要： SQL语句1、 查找表中某一字段有重复的记录select DATAID, UT, count(UT) as num from sci148_2 group by UT having count(UT) > 1 order by num;Java程序1、 控制小数显示位数Import java.text.DecimalFormat;DecimalFormat xiaoshu = new DecimalFormat("0.000");//控制小数位数，小数点后3位Double d = 1.3234;System.out.println(xiaoshu.format(d)) 阅读全文