Determine if the first occurence of a record was during a given period

[nicnad]

Hi,

I have a table like the following :

NAME	ALERT_DATE
bob	2010-12-10
nicolas	2013-06-20
nicolas	2013-06-30
bob	2012-10-10
william	2013-07-01
guy	2011-11-10
william	2013-07-02
julie	2013-07-10
julie	2013-07-13

I would like to write a query so that I only keep the records where the first alert for each name was between the 2013-05-01 and 2013-07-05. So I would like to kill all the name that had an alert that was before 2013-05-01 and all the records where the first alert was after 2013-07-05. For each of those name I would like to keep only the first alert.

So the end result would be :

Name	ALERT_DATE
nicolas	2013-06-20
william	2013-07-01

Could you please help me write that query?

Thank you for your help and time.

[PaigeMiller · Accepted solution]

It's pretty easy if you first sort by name and alert_date.

Then, a simple datastep works

data whatever;

     set whatever;

     by name;

     if first.name and alert_date>'01MAY13'd and alert_date<'05JUL13'd; /* Assumes alert_date is numeric date */

run;

[nicnad]

Works like a charm and makes much sense.

Thank you very much for your help!