r,datetime,vector,seconds,minute

From help("difftime") If units = "auto", a suitable set of units is chosen, the largest possible (excluding "weeks") in which all the absolute differences are greater than one. units = "auto" is the default. So for a difference of 1 and 61 seconds, if you were to choose minutes, difftime(c((t+1),...

postgresql,time,group-by,minute

This may be a bit sub-optimal, but it works. The recursive query detects the start- and stop- times of the intervals; the count(*) scalar subquery counts the number of original records within each interval. WITH RECURSIVE rr AS ( SELECT 1::integer AS num , MIN(tscol) AS starter , MIN(tscol) +...

You could get the date/time and strip of the date part. That time can be compared to other time values. In the code below, I calculate the values in seconds from midnight for the current time, 8:30 and 21:15, and then the if becomes quite simple: $time = time ()...

I don't know why the logic was inverted in the first if(). I think I was confused. Apologies for that. create table temp_table1 as select t.* from (select t1.*, (@rn := if(@prevd = date and minute(time) = @prevm, @rn + 1, if(@prevd := date, if(@prevm := minute(time), 1, 1), 1)...

I would suggest subtracting 30 minutes for the hour comparison: select count(*), YEAR(date), MONTH(date), DAY(date) from table where YEAR(date) = 2014 AND HOUR(date - interval 30 minute) between 08 and 17 group by YEAR(date), MONTH(date), DAY(date); Note that the upper limit is 17, assuming that the interval ends just before...

You can do what you want with delete and aggregation: delete bt from bigtable bt join (select date, min(time) as time from bigtable group by date, hour(time), minute(time) ) btt on btt.date = bt.date and hour(bt.time) = hour(btt.time) and minute(bt.time) = minute(btt.time) and bt.time <> btt.mintime; I am not promising...

javascript,math,time,seconds,minute

Use Math.round() for subtracting 6.75 from travelTime. This is will round to the nearest whole number.

java,android,jodatime,period,minute

This is documented behaviour, check out the Javadoc for the plus(Period) function: /** * Returns a new period with the specified period added. * <p> * Each field of the period is added separately. Thus a period of * 2 hours 30 minutes plus 3 hours 40 minutes will produce...