Date:         Tue, 3 Oct 2006 18:41:49 -0500
Reply-To:     SAS_learner <proccontents@GMAIL.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         SAS_learner <proccontents@GMAIL.COM>
Subject:      Re: Surprising retain feature
Comments: To: avi <aviben@bezeqint.net.il>
In-Reply-To:  <1159915612.212597.248910@k70g2000cwa.googlegroups.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

I believe there is some good paper out there on
http://www.lexjansen.com/sugi/ about this, but when I was preparing myself
for base cert. I read this SET, MERGE , UPDATE, SUM (I think there are
couple of more ) act as Retain because of the  way the data step processing
works.Why ........... Look out for key word on  PDV (program data vector )

thanks



On 10/3/06, avi <aviben@bezeqint.net.il> wrote:
>
> Hello,
>
> Though an quite experienced user of SAS, i was quite surprised to learn
> that in some cases, observations retain their values from one obs to
> another, without specifying the RETAIN statement
> ("When variables are read with a SET, MERGE, or UPDATE , The variables
> retain their values until new values become available").
>
> Could someone explain exactly what and why it happens and the way to
> overcome the problem thaht has caused some disturbing results in one of
> my applications?
>
>
> Thaks a lot
> Avi
>