date-of-birth

I am using data.table for the first time. I have a column of about 400,000 ages in my table. I need to convert them from birth dates to ages. What is the best way to do this? Gregor From the comments of this blog entry , I found the age_calc function in the eeptools package. It takes care of edge cases (leap years, etc.), checks inputs and looks quite robust. library(eeptools) x <- as.Date(c("2011-01-01", "1996-02-29")) age_calc(x[1],x[2]) # default is age in months [1] 46.73333 224.83118 age_calc(x[1],x[2], units = "years") # but you can set it to years [1] 3.893151 18.731507 floor(age_calc(x

I work with a Postgres database. This DB has a table with users, who have a birthdate (date field). Now I want to get all users who have their birthday in the upcoming week.... My first attempt: SELECT id FROM public.users WHERE id IN (lange reeks) AND birthdate > NOW() AND birthdate < NOW() + interval '1 week' But this does not result, obviously because off the year. How can I work around this problem? And does anyone know what happen to PG would go with the cases at 29-02 birthday? We can use a postgres function to do this in a really nice way. Assuming we have a table people , with a date

How should I store Birthdate's in MySQL so that I can easily update everyone's Age on a daily basis via a Cron Job? Does it even make sense to store the Age AND the Birthdate so that when searches involving the Age are made, I don't have to calculate each Age on-the-fly and waste CPU resources? If so, how should I 1) store the Birthdate, and 2) calculate the Age each day? I can imagine the daily cron script first filtering out the user's whose Birthdate month is not the current month, then filtering out the user's whose Birthdate day is not the current day, and then incrementing by one the age