The OP answered this question to change the default timezone for a single instance of a running JVM, set the user.timezone system property: java -Duser.timezone=GMT … <main-class> If you need to set specific time zones when retrieving Date/Time/Timestamp objects from a database ResultSet, use the second form of the getXXX methods that takes a Calendar … Read more
GMT does not adjust for Daylight saving time (DST). You can hear it from the horse’s mouth on this web site. Add this line of code to see the source of the problem: Console.WriteLine(TimeZoneInfo.FindSystemTimeZoneById(“GMT Standard Time”).SupportsDaylightSavingTime); Output: True. This is not a .NET problem, it is Windows messing up. The registry key that TimeZoneInfo uses … Read more
Although the gmdate functions are available. If you are using PHP 5.2 or greater, then consider using the DateTime object. Here’s code to switch to GMT $date = new DateTime(); $date->setTimezone(new DateTimeZone(‘GMT’)); and back to the default timezone… $date = new DateTime(‘2011-01-01’, new DateTimeZone(‘GMT’)); $date->setTimezone(new DateTimeZone(date_default_timezone_get())); Using the DateTime object lets your create a datetime, … Read more
As Jimmy points out you can use timezone transitions, but this is not available on PHP <5.3. as dateTimeZone() is PHP>=5.2.2 but getTransitions() with arguments is not! In that case here is a function that can give you timezone data, including whether in DST or not. function timezonez($timezone=”Europe/London”){ $tz = new DateTimeZone($timezone); $transitions = $tz->getTransitions(); … Read more
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init]; dateFormatter.dateFormat = @”yyyy-MM-dd’T’HH:mm”; NSTimeZone *gmt = [NSTimeZone timeZoneWithAbbreviation:@”GMT”]; [dateFormatter setTimeZone:gmt]; NSString *timeStamp = [dateFormatter stringFromDate:[NSDate date]]; [dateFormatter release];
Astronomy versus Atomic clock By the original definitions the difference is that GMT (also officially known as Universal Time (UT), which may be confusing) is based on astronomical observations while UTC is based on atomic clocks. Later GMT has become to be used at least unofficially to refer to UTC, which blurs the distinction somewhat. … Read more
Odds are good you did the right stuff on the back end in getting the date, but there’s nothing to indicate that you didn’t take that GMT time and format it according to your machine’s current locale. final Date currentTime = new Date(); final SimpleDateFormat sdf = new SimpleDateFormat(“EEE, MMM d, yyyy hh:mm:ss a z”); … Read more
mySQL has DATE_SUB(): SELECT DATE_SUB(column, INTERVAL 3 HOUR)…. but would it not be better to try and sort out the underlying time zone issue instead?
All I needed was this : SimpleDateFormat sdf = new SimpleDateFormat(“yyyy.MM.dd HH:mm:ss”); sdf.setTimeZone(TimeZone.getTimeZone(“GMT”)); SimpleDateFormat sdfLocal = new SimpleDateFormat(“yyyy.MM.dd HH:mm:ss”); try { String d = sdf.format(new Date()); System.out.println(d); System.out.println(sdfLocal.parse(d)); } catch (Exception e) { e.printStackTrace(); //To change body of catch statement use File | Settings | File Templates. } Output : slightly dubious, but I want … Read more
Answer is: It depends. In total your database has three time zones Your session time zone: SESSIONTIMEZONE This you can change by ALTER SESSION SET TIME_ZONE=… at any time. It is relevant for result of CURRENT_DATE LOCALTIMESTAMP CURRENT_TIMESTAMP It is also the target time zone when you do CAST({TIMESTAMP/DATE without any timezone} AS TIMESTAMP WITH … Read more