如何实现这样的查询?

[yibin2006]

publishdate
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2006-02-14 15:28:00
2006-03-02 13:17:00
2006-03-02 22:53:00
2006-03-11 18:45:00
2006-03-11 22:46:00
2006-03-12 14:07:00
2006-03-12 17:20:00
2006-03-13 12:19:00
2006-03-13 17:32:00
2006-03-13 18:28:00
2006-03-13 21:48:00
2006-03-14 13:53:00
2006-03-14 20:24:00
2006-03-14 23:06:00
2006-03-14 23:39:00
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2006-03-15 22:43:00
2006-03-16 12:10:00
2006-03-16 18:19:00
2006-03-17 11:47:00
2006-03-17 18:44:00
2006-03-20 13:27:00
2006-03-21 22:47:00
2006-03-21 23:03:00
2006-03-22 10:05:00
2006-03-22 19:30:00
2006-03-22 20:32:00
2006-03-23 15:02:00
2006-03-24 16:24:00
2006-03-25 10:51:00
2006-03-25 11:55:00
2006-03-25 14:15:00
2006-03-26 15:26:00
2006-03-26 16:00:00
2006-03-26 16:29:00
2006-03-27 09:12:00
2006-03-28 09:56:00
2006-03-28 10:13:00
2006-03-28 14:51:00
2006-03-28 15:43:00
2006-03-29 15:20:00
2006-03-30 21:34:00
2006-04-01 09:58:00
2006-04-01 14:04:00
2006-04-01 21:20:00
2006-04-04 20:16:00
2006-04-05 09:52:00
2006-04-05 13:59:00
2006-04-05 19:50:00
2006-04-06 17:11:00
2006-04-06 19:51:00
2006-04-07 10:33:00
2006-04-10 14:14:00
2006-04-10 16:32:00
2006-04-11 12:20:00
2006-04-12 08:52:00
2006-04-13 15:46:00
.............
这是表中记录的其中一个字段
能否实现这样？
2006-03
2006-04
只取记录中存在的年-月?

[冷箫轻笛]

select convert(varchar(7),publishdate,120) from tablename

[hjw01592]

select convert(varchar(7),publishdate,120) as '年月' from tablename

[itblog]

select convert(char(7),publishdate,120) from 表

[yibin2006]

可能没有表述清楚
楼上各位的代码执行以后的效果是：
-------
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-03
2005-04
2005-04
2005-04
2005-04
2005-04
2005-04
2005-04
2005-04
2005-04
2005-04
2005-04
2005-04
2005-04
2005-04
2005-05
2005-05
2005-05
2005-05
2005-05
2005-05
2005-05
2005-05
2005-05
2005-05
2005-06
2005-06
2005-06
2005-06
2005-06
2005-06
2005-06
2005-06
2005-06
2005-07
2005-07
2005-07
2005-07
2005-08
2005-08
2005-08
2005-08
2005-08
2005-08
2005-09
2005-09
2005-09
2005-09
2005-09
2005-09
.......
没有过滤掉重复的日期哦
要得到的是
2006-03
2006-04
相当于distinct的效果

[张散]

select distinct ptime from (select convert(char(7),publishdate,120) as ptime from 表) tab

[冷箫轻笛]

加个distinct

select distinct convert(varchar(7),publishdate,120) from tablename

[paoluo]

Select Distinct Convert(Varchar(7),publishdate,120) As publishdate From TableName