Thank you both ata_null_ and Howard for the clear explanation. Another lesson learned.

-----Original Message----- From: SAS(r) Discussion [mailto:SAS-L@LISTSERV.UGA.EDU] On Behalf Of Howard Schreier <hs AT dc-sug DOT org> Sent: Monday, April 16, 2007 6:20 PM To: SAS-L@LISTSERV.UGA.EDU Subject: Re: arrays

On Mon, 16 Apr 2007 16:48:35 -0400, data _null_; <datanull@GMAIL.COM> wrote:

>In this case where there is no MASTER the transaction data set is used >as the MASTER. Hence UPDATE have(obs=0) have; SAS is happy to have a >MASTER data set with 0 observations but it must exist, for UPDATE to >work properly.

Moreover, the satellite variables are not needed on the master side. So an even more spare implementation of this technique is

data want; update have (obs=0 KEEP = ID ) have; by id; run;

> > >On 4/16/07, Huang, JS <Huang.JS@principal.com> wrote: >> Mogens: >> >> Can you explain what role dose "obs=0" play in the update statement? >> >> Thanks, >> >> -----Original Message----- >> From: SAS(r) Discussion [mailto:SAS-L@LISTSERV.UGA.EDU] On Behalf Of >> Mogens A. Krogh >> Sent: Monday, April 16, 2007 2:56 PM >> To: SAS-L@LISTSERV.UGA.EDU >> Subject: Re: arrays >> >> Dear Sas_learner, >> The simple solution would be (learned it here on the SAS-L): >> >> data want; >> update have (obs=0) have; >> by id; >> run; >> >> regards >> Mogens A. Krogh >> PhD-student, DVM >> www.life.ku.dk >> >> >> -----Message Disclaimer----- >> >> This e-mail message is intended only for the use of the individual or

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