...
Statememt stmt = yourConnection.createStatement(ResultSet.TYPE_FORWARD_ONLY);
ResutSet rs = stmt.executeQuery("select 时间,交易量 from 表 where convert(时间, char(10), 112) between '2008-03-01' and '2008-03-22' order by 时间"); //convert的参数不是112就是120，忘了，好久没用SQLServer，LZ自己查一下帮助
Calendar c1 = new GregorianCalendar(2008, 2, 1);
Calendar c2 = new GregorianCalendar(2008, 2, 22);
Map<String, Integer> map = new HashMap<String, Integer>();
//SimpleDateFormat sf = new SimpleDateFormat("yyyy-MM-dd");
String s1="", s2="";
int v = 0;
while (c1.before(c2) == false) {
    s1 = String.format("%1$tF", c1.getTime());
    if (s1.equals(s2)) {
        map.put(s2, v);
        continue;
    }
    if (rs.next()) {
        s2 = String.format("%1$tF", rs.getDate("时间")); //时间为null字段应该没有吧，重复的时间如果有的话以下要修改，这里以不重复处理
        v = rs.getInt("交易量");
        if (s1.equals(s2)) {
            map.put(s2, v);
        } else if (s1.compareTo(s2) < 0) { //s1>s2的可能没有吧，按LZ的数据
            map.put(s1, 0);
        }
    } else {
        map.put(s1, 0);
    }
    c1.add(Calendar.Date, 1);
}

for (Map.Entry<String, Integer> entry : map.entrySet()) {
    System.out.printf("%s, %d", entry.getKey(), entry.getValue());
}


...

------解决方案--------------------
给你提供个思路，先生成一张你想要的日期段的表，然后用这张表去LEFT JOIN 你真正的数据表，按日期字段进行关联即可
SQL code

DECLARE   @t TABLE ( Times DATETIME)
DECLARE @starttiem DATETIME,@endtime DATETIME 
SELECT @starttiem = '2009-03-01', @endtime ='2009-03-22'     
WHILE   @starttiem   &lt;=   @endtime   
  BEGIN   
      INSERT   INTO   @t   
      SELECT   @starttiem   
      SET   @starttiem   =   CONVERT(VARCHAR(10),Dateadd(DAY,1,@starttiem),120)
  END
select * from @t

------解决方案--------------------
生成时间基表，左连即可。


SQL code
DECLARE @st DATETIME,@et DATETIME,@n INT
SELECT @st='2009-3-1',@et='2009-3-22',@n =DATEDIFF(dd,'2009-3-1','2009-3-22') + 1 

SET ROWCOUNT @n
SELECT ID=IDENTITY(INT),dt = CAST(NULL AS DATETIME)  INTO #1 FROM sysobjects,syscolumns
UPDATE #1 SET dt = DATEADD(dd,ID-1,@st)
SET ROWCOUNT 0

SELECT a.dt,ISNULL(sm,0) 交易量 FROM #1 a
LEFT JOIN 
    (
    SELECT CONVERT(