Adding days to a DATETIME value?

[TurnTheBacon]

I have a macrovariable called &filterdate_start. It's DATETIME20 and has the value 26NOV2012:00:00:00.

I need a new macrovariable called &filterdate_end to equal &filterdate_start + 2 days, with the value 28NOV2012:00:00:00.

What's the most practical way to add 2 days to a DATETIME20 value?

[LinusH · Accepted solution]

If you want the same time of day, just add 2 * 24 * 60 * 60.

[Robert_Bardos]

I'd use one of SAS's most powerful date/datetime functions: INTNX

Somewhat like

%let filterdate_end = %sysfunc( intnx( dtday, "&filterdate_start"dt, 2 ) , datetime20. ) ;

Two assumptions here: &filterdate_start is the formatted datetime value, &filterdate_end is expected to be in datetime20. format.

If not then

%let filterdate_end = %sysfunc( intnx( dtday, &filterdate_start, 2 ) ) ;

will do and return the result as the number of seconds since SAS epoch (formatting then left to you).