topic Re: Understanding the code for Appending several datasets in SAS Procedures

Understanding the code for Appending several datasets

robertrao — Wed, 03 Apr 2013 20:01:34 GMT

Hi,

I have a couple of questions in the following link...

http://support.sas.com/kb/48810

proc contents data=abc._all_ out=abccont(keep=memname) noprint; /*what does the memname refer to*/

run;

ALSO

%macro combdsets;

%do i=1 %to &count;

proc append base=new data=abc.&&name&i force; /*after running this macro step "NEW" dataset is created which has all the datasets???*/

run;

%end;

%mend combdsets;

Thanks

Re: Understanding the code for Appending several datasets

Linlin — Wed, 03 Apr 2013 20:33:44 GMT

Hi,

try the code below.

libname abc "c:\temp"; /* change the directory if necessary. there should not be any other datasets in this dir. */
data abc.data1 abc.data2 abc.data3;
set sashelp.class;
run;
proc contents data=abc._all_ out=abccont(keep=memname) noprint;run; /* memname is dataset name */
proc sort data=abccont nodupkey;
by memname;
run;

data _null_;
set abccont end=last;
call symputx(cats('name',_n_),memname);
if last then call symputx('count',_n_);
run;
%put _user_; /* allow you to see the macro variables in log file */
%macro combdsets;
%do i=1 %to &count;
proc append base=new data=abc.&&name&i force; /*after running this macro step "NEW" dataset is created which has three datasets(data1,data2,data3) */
run;
%end;
%mend combdsets;
%combdsets

Re: Understanding the code for Appending several datasets

robertrao — Wed, 03 Apr 2013 20:44:31 GMT

Hi Linlin..

In the below abcount is the dataset name...i still have questions about memname...

Could you explain a little bit

proc contents data=abc._all_ out=abccont(keep=memname) noprint;run; /* memname is dataset name */

proc sort data=abccont nodupkey;

by memname;

run;

Also if I am sure that there are no duplicates of datasets can I ignore the PROC CONTENTS and the PROC SORT?

Re: Understanding the code for Appending several datasets

Reeza — Wed, 03 Apr 2013 20:47:23 GMT

Run it without the keep= and then with the keep = to see what happens.

Re: Understanding the code for Appending several datasets

Linlin — Wed, 03 Apr 2013 20:52:07 GMT

abccont is the dataset name just created. memname is a variable of dataset abccont, the values of memname are all the dataset names in the library.

Re: Understanding the code for Appending several datasets

robertrao — Wed, 03 Apr 2013 20:52:42 GMT

Hi,

Yes I did run..

So MEMNAME is a variable produced with the CONTENTS PRocedure which contains the names of the datasets??????

Regards

Re: Understanding the code for Appending several datasets

robertrao — Wed, 03 Apr 2013 21:10:57 GMT

One last question:

Is it compulsary that I run the contents and the SOrt????

What is the PROC CONTENTS role here in the code?????

All the datasets I have now are got after running the same Macro

Regards

Re: Understanding the code for Appending several datasets

Reeza — Wed, 03 Apr 2013 22:00:33 GMT

Proc contents creates the list of datasets to append from the library.

Test what you need in your circumstances by deleting all intermediary files created and then running sections and see what happens.

IMO the proc sort isn't needed, because SAS won't allow duplicate names in a library, but the remaining steps are.

Re: Understanding the code for Appending several datasets

Linlin — Wed, 03 Apr 2013 23:56:13 GMT

you have to use proc sort.

below is the output without proc sort:

libname abc "c:\temp"; /* change the directory if necessary. there should not be any other datasets in this dir. */

data abc.data1 abc.data2 abc.data3;

set sashelp.class;

run;

proc contents data=abc._all_ out=abccont(keep=memname name) noprint;run; /* memname is dataset name */

proc print data=abccont;run;

Obs MEMNAME NAME

1 DATA1 Age

2 DATA1 Height

3 DATA1 Name

4 DATA1 Sex

5 DATA1 Weight

6 DATA2 Age

7 DATA2 Height

8 DATA2 Name

9 DATA2 Sex

10 DATA2 Weight

11 DATA3 Age

12 DATA3 Height

13 DATA3 Name

14 DATA3 Sex

15 DATA3 Weight

Re: Understanding the code for Appending several datasets

Reeza — Thu, 04 Apr 2013 01:13:28 GMT

That's what I get for not running the code

This isn't the type of macro you need to append monthly datasets though. what you need then is something like the following:

%macro append_monthly(new_data=);

proc append base=old_data data=&new_data;

run;

%mend;

Then you call it each month with the new file.

Re: Understanding the code for Appending several datasets

robertrao — Thu, 04 Apr 2013 13:52:46 GMT

Hi,,

Until I append all the datasets present currently in the library to one single dataset I need to go with

%macro combdsets;

%do i=1 %to &count;

proc append base=new data=abc.&&name&i force;

run;

%end;

%mend combdsets;

After I do that every month fresh data is appended by :

%macro append_monthly(new_data=);

proc append base=old_data data=&new_data;

run;

%mend;

IS IT RIGHT?????

Re: Understanding the code for Appending several datasets

robertrao — Thu, 04 Apr 2013 14:41:00 GMT

Hi,

Is my understanding of this topic correct?

Regards

Re: Understanding the code for Appending several datasets

Linlin — Thu, 04 Apr 2013 15:17:51 GMT

I think so.

make sure your "old_data" dataset is the same as your "new" dataset (the cumulative one you created by running your macro);

%macro combdsets;

%do i=1 %to &count;

proc append base=new data=abc.&&name&i force;

run;

%end;

%mend combdsets;

After I do that every month fresh data is appended by :

%macro append_monthly(new_data=);

proc append base=old_data data=&new_data;

run;

%mend;

Re: Understanding the code for Appending several datasets

Reeza — Thu, 04 Apr 2013 17:31:38 GMT

Read the doc or try it.

Base SAS(R) 9.2 Procedures Guide

Overview: APPEND Procedure

The APPEND procedure adds the observations from one SAS data set to the end of another SAS data set.