Date:         Mon, 18 Jul 2005 18:22:37 -0700
Reply-To:     Rob_W <weyrauch_r@YAHOO.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Rob_W <weyrauch_r@YAHOO.COM>
Organization: http://groups.google.com
Subject:      Create, append or delete datasets in macro
Comments: To: sas-l@uga.edu
Content-Type: text/plain; charset="iso-8859-1"

Goal:
I need to check if a dataset exists (eg: FileA), if it does then I need
to append another file to it (eg: FileB).

If FileA does not exist, then I need to create it based on the data in
FileB.

Question:
Using a macro called from a datastep, how can you check if a file
exists, and then conditionally either append or create the dataset as
needed?

Code:
The following is the code that obviously does not work.  I included it
here in hopes that it clarify what I am trying to accomplish.  Thanks
for the input....

************************
************************

 %MACRO AppendTempDs(CheckFile=, CurrentFile=) ;

                %IF %SYSFUNC(FILEEXIST( &CheckFile )) %THEN
                        %DO;
                                PROC APPEND BASE=&CheckFile
                                DATA=&CurrentFile ;
                                RUN;
                        %END;
                %ELSE
                        %DO;
                                DATA &CheckFile ;
                                SET &CurrentFile;
                                RUN ;
                   %END;

            PROC DATASETS ;
                        DELETE &CurrentFile ;
            RUN;

 %MEND  AppendTempDs ;

 **************************;
 ** Sample call to macro **;
 **************************;

 DATA;

        %AppendTempDs(CheckFile="FileA" , CurrentFile="FileB" ) ;

 RUN;

************************
************************