这是经过测试的解决方案.

THIS IS THE TESTED SOLUTION.

update personnaldetails
set dbdate = dateadd(day,(29-datepart(dd,dbdate)),dbdate)

I不知道这是否可以轻松地使用SQL来实现.我将放置SELECT查询以获取列表，然后对于每条记录，将其提取为DateTime类型.然后使用更新的日期进行更新.

修改DateTime的示例:

I do not know if this can be easly use SQL to achive this. I would put SELECT query to get a list and then for each record I would fetch into DateTime type. Then update with updated date.

Example to modify DateTime:

DateTime dt = DateTime.Now.Date.AddDays(2);
dt = dt.AddMonth(1);
dt = dt.AddYear(1);

您知道，如果您使用google，则编码会更快:

http://msdn.microsoft.com/en-us/library/ms186724.aspx [ ^ ]

You know, your coding would go A LOT faster if you used google:

http://msdn.microsoft.com/en-us/library/ms186724.aspx[^]