LISTSERV at the University of Georgia
Menubar Imagemap
Home Browse Manage Request Manuals Register
Previous messageNext messagePrevious in topicNext in topicPrevious by same authorNext by same authorPrevious page (September 2008, week 2)Back to main SAS-L pageJoin or leave SAS-L (or change settings)ReplyPost a new messageSearchProportional fontNon-proportional font
Date:         Mon, 8 Sep 2008 14:44:23 -0600
Reply-To:     Alan Churchill <savian001@GMAIL.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Alan Churchill <savian001@GMAIL.COM>
Subject:      Re: SAS data file format ?
Comments: To: Capra Hircus <capra.hircus@ORANGE.FR>
In-Reply-To:  <48c58c35$0$874$>
Content-Type: text/plain; charset="us-ascii"

Look at the SAS OleDb drivers for Windows. They are free and make SAS files appear as an OleDb compliant datasource. SAS does not need to be installed to use this.


Alan Churchill Savian

-----Original Message----- From: SAS(r) Discussion [mailto:SAS-L@LISTSERV.UGA.EDU] On Behalf Of Capra Hircus Sent: Monday, September 08, 2008 2:34 PM To: SAS-L@LISTSERV.UGA.EDU Subject: Re: SAS data file format ?

Mary wrote: > Capra, > > One trend I've certainly seen in the health care industry, not just in = > SAS but also in moving data between health care systems such as IDX/GE = > to EPIC, is to write data out as XML and then have the recieving system = > read data in as XML. In SAS, one might write it out as follows: > > libname trans xml 'c:\temp\analysis_set.xml' xmltype=3Dgeneric = > tagset=3Dsasxmxsd=20 > XMLMETA=3DSCHEMADATA; > data trans.analysis_set; > set work.analysis_set; > run; > > > It would seem, if you are willing to devote your time to open code,

I'd like to be useful.

> that = > perhaps a more valuable use of your time would be to ensure that the = > packages your users use, such as R, are able to utilize XML with = > embedded XSD; where it is the XSD that I've found that contains the = > metadata that defines the informats of the variables; thanks to Alan = > Churchill for explaining this.

It's an interesting idea.

> Then you could simply export your SAS datasets as above.

XML is certainly a good thing, but :

* at work I have datasets as huge as 1.4G (I said 900M in another post but after checking it's 1.4G). It may yield a rather large xml file. * if I write a program for personnal use and hopefully for other people, I cannot assume anybody has SAS to convert files. That's a point I don't understand : you are not the first to tell me to convert my files with SAS, but that's precisely the problem, getting a SAS file without SAS. That's a problem I had before getting this job, where I do have SAS now. If I can help someone with finding the file format, why not ? It's probably not easy though, otherwise R would already have that. (after a first look, data is rather easy to see in hexadecimal dumps, but it's exact location in the file does not look very deterministic for the moment :-))

Oh, and btw, R is really out of question to manage 1.4G files. Or even 60M. That's a problem often seen with programs that load entire files in memory.

Just to show some limitation (useful when trying to find informations with no specs at hand) : SAS can write a 5 billion lines file, though it seems to have a problem to store the number of rows : as far as I can tell, it's limited to signed 32 bit integers.

Back to: Top of message | Previous page | Main SAS-L page