Impact of Daylight Saving Time (DST)

Report · Feb 19, 2007

Hi

I want to know the impact of the Daylight Saving Time (DST). In next month some states going to change their timings, by adjustings 1 hour.
How this is going be effect on the CF applications as well as batch jobs.
I have an time entry system, will there is any effect on this?
could any one can explain on this.

Report · Feb 19, 2007

vkunirs wrote:
> I want to know the impact of the Daylight Saving Time (DST). In next month
> some states going to change their timings, by adjustings 1 hour.
> How this is going be effect on the CF applications as well as batch jobs.
> I have an time entry system, will there is any effect on this?
> could any one can explain on this.

if you don't update for the DST changes your datetimes will be off by one hour.
this includes cf, your OS, your database server, etc. of course this only
matters if your server/application uses US timezone but if it does, by all means
do the updates.

Report · Feb 20, 2007

Hi

Yes.. my application is using the US timezone.
does i just need to change the time..thats it?
or else...does i need to do any other changes?
what about the transaction done in between that time.?
will the batch jobs executes twice? if then what i need to do?
and even for later purpose also does i need to change the batch job timings to effect the DST changes.

Report · Feb 20, 2007

vkunirs wrote:
> Hi
>
> Yes.. my application is using the US timezone.
> does i just need to change the time..thats it?

i wouldn't just simply "change the time". apply the OS, cf, etc. patches & the
server will take of all this.

> what about the transaction done in between that time.?

not sure i understand.

> will the batch jobs executes twice? if then what i need to do?

no, if you have one scheduled right on the DST cusp it might not fire off that
one time.

> and even for later purpose also does i need to change the batch job timings
> to effect the DST changes.

no, apply the patches.

btw what ver of cf?

Report · Feb 20, 2007

Check out http://www.sargeway.com/blog/index.cfm/2007/1/22/ColdFusion-DST for more information. On March 11, there will be no 2:00:00 - 2:59:59 a.m. Any chron job scheduled during that period will not run. And beware of the DateConvert( ) function.

Report · Feb 20, 2007

Hi

thats nice link to look it.
Can I get impactness on JRun/Apache also, because i am running my CF on this.

Report · Feb 20, 2007

Ben Forta's blog has additional information - http://www.forta.com/blog/index.cfm/2007/2/6/ColdFusion-And-Daylight-Savings-Time-Changes. Also, the Adobe KB at http://www.adobe.com/cfusion/knowledgebase/index.cfm?id=d2ab4470 addresses the JRun issue. Finally, Apache issues are found at http://cookbook.sitellite.org/index/sitewiki-app/show.DaylightSavingsTimeChanges

Report · Feb 20, 2007

Here is a page that shows the change in behavior of DateDiff. I use it to test that the patches were installed properly. It shows different output before and after applying the patches.

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">

<html>
<head>
<title>Untitled</title>
</head>

<body>

Hours between 3/10 and 3/12: <CFOUTPUT>#DateDiff( "h", "3/10/2007 0:0:0", "3/12/2007 0:0:0" )#</cfoutput>
 
Answer should be: 47 (?)
 
Hours between 3/31 and 4/2: <CFOUTPUT>#DateDiff( "h", "3/31/2007 0:0:0", "4/2/2007 0:0:0" )#</cfoutput>
 
Answer should be: 48

</body>
</html>

Report · Feb 21, 2007

Hi

than Q very much to all.
first i need to update my CF JRE ver. then it will works automatically.

thanks

Report · Feb 21, 2007

Applications which are using the coldfusion server for timed events are using server time. Where are your servers located? If they are in Arizona, Arizona does not recognize daylight savings time.

Adobe Community

Impact of Daylight Saving Time (DST)