Could pls explain why I' not able to get valid result ( with precision to miliseconds ) after doing this (adding 7hrs to date):

```
select getdate() as dt into #t1
select dt, dt+(7.*60/1440) as dt_new from #t1

```

I got:

```
dt                      dt_new
2010-10-25 04:56:33.640 2010-10-25 11:56:33.580

```

As you can see there is difference in 60ms for dt\_new - WHY?
AFAIR I WAS able to do this sort of things in Oracle 10g - even with minutes:
**`date + 5/1440`** -to produce 5-min periods of datetime.

***UPD:***

My mistake - the CORRECT way of doing this is:

```
select getdate(), getdate()+(convert(float, 5)/1440) as dt_new 

```

I suppose there is wrong implicit convertion choosen by Ms Sql server.

**UPD2:**
Thanks for replies, but my point was "arifmetic" method - because there are cases when calculating dates ***without*** `dateadd` really improves Query Plan - by eliminating Table scan that is the case with Dateadd and other functions. 
Anyway it works - thanks!