Date:         Wed, 10 Jul 2002 18:46:14 -0400
Reply-To:     Jan Padilla <jan.padilla@MINDSPRING.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Jan Padilla <jan.padilla@MINDSPRING.COM>
Subject:      Re: A datastep question...
Comments: To: Benjamen Meyer <bmeyer67@CALVIN.EDU>

If you put the keep option on the output dataset, you don't need to keep
the variables used for subsetting.

DATA InputData(KEEP=ID1 ID2);
        SET DB.Input(WHERE=(ID3=&X);
        RUN;

On Wed, 10 Jul 2002 16:39:00 -0400, Witness <bmeyer67@CALVIN.EDU> wrote:

>Well, not necessarily a datastep, but...
>
>I have been starting to use WHERE clauses in set statements to limit my
>data instead of using the subsetting-IF. However, I still find that I
>need to have the COLUMN that I am using in the WHERE clause to in order
>to run the step.
>
>Example:
>
>DATA InputData;
>        SET DB.Input(KEEP=ID1 ID2 ID3 WHERE=(ID3=&X);
>        RUN;
>
>If I needed ID3 later on, then I wouldn't mind having to have it in the
>returned columns. However, I don't and it takes up space. (I remove it
>at the next time that I subset my data, such as a PROC MEANS procedure.)
>
>Now, if I were to implement this SQL, I don't need to have the column
>ID3 there.
>
>Example:
>
>PROC SQL;
>        CREATE TABLE InputData AS
>                SELECT ID1,ID2 FROM DB.Input WHERE ID3=&X;
>        QUIT;
>
>Is there some way that with the DATA step's (or PROCs if it were to be
>done there) that I could drop a column but use it in the WHERE?
>
>Note: This is not a question of SAS vs. SQL. But a question of SAS in
>how to do it, or why can't it be done?  If I were worried about space,
>the SQL may be more appealing even though it takes a little longer to
>run, at least in my test scenario from one of my scripts. (Difference in
>time is 8.57 seconds real time, and 9.98 seconds CPU time. That also
>includes a sort, and the data step is done through a PROC SORT
>statement.)
>
>Thanks,
>
>Benjamen R. Meyer