Date: Tue, 15 Dec 2009 14:01:59 -0500
Reply-To: Jonathan Goldberg <jgoldberg@BIOMEDSYS.COM>
Sender: "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From: Jonathan Goldberg <jgoldberg@BIOMEDSYS.COM>
Subject: Re: Information on what processing SAS is doing behind the
I suggest you look at the "SAS Language Concepts" documentation. It's a
printed volume if you're lucky enough to have print; otherwise, it's a
section of the on-line documentation.
I don't think it would have told you about merge. However, it has a great
deal of background information it's hard to find elsewhere. For instance,
if you do a lot of SAS eventually the information of how SAS handles
dates, times, and date-time intervals will be indespensible. There is all
too much slow, pedantic, bit-by-bit information in there. The mastery of
this information is one of the main things that seperate proficient SAS
programmers from experts.
SUGI and SAS Global Forum papers are, as noted, an excellent source. I
suggest paying special attention to anything written by Ian Whitlock or
Paul Dorfman. Their SAS-L postings are also illuminating.
Good luck with your SAS endeavors. SAS-L will try to help where possible.
On Tue, 15 Dec 2009 13:41:28 +0100, js8765 <js8765@GOOGLEMAIL.COM> wrote:
>I'm learning SAS at the moment and in general I find the documentation
>provided by SAS to be very thorough and easy to follow. However, I feel
>I would be able to learn a lot quicker and understand the different
>aspects better if I could find more information on what SAS is actually
>doing behind the scenes in each case.
>For example, when I eventually found information on the way SAS
>processes match-merge operations (i.e. information on how the
>observation pointer moves through the different data sets, etc.),
>suddenly everything became clear and it was easy to predict what would
>happen in different situations.
>Another example is the UNIQUE option used when modifying data using an
>index. It finally made much more sense when I discovered somewhere that
>the data set normally only returns to the top of the index when the
>value of key variables changes between execution of the statement with
>the KEY= option.
>Maybe I'm not looking in the right place, or maybe such a place does not
>exist but I find this type of information hard to come by in the SAS
>documentation. So I was wondering if anyone knows of any good source
>with information on how SAS processes different steps. Information that
>would help explain such things as why when modifying using an index we
>have to explicitly specify the updates wanted whereas that is not
>necessary when no index is used. There's no need to answer this concrete
>example (I'm not even sure if the statement is correct!) I'd just like
>general information on how the black box SAS ticks inside.
>Thanks in advance for any help!