topic How to import multiple files and concatenate them into one file in SAS Programming

How to import multiple files and concatenate them into one file

MILKYLOVE — Thu, 29 Sep 2022 11:19:42 GMT

Hello,

I am new to SAS and I have an issue:

I have a directory (C:/mydir/myfiles) where I have many csv files (the number is not constant).

I have to import these files and concatenate them (in no particular order), to get a final csv file. Note that the csv files have identical columns, data types etc.

Example:

myfile_V1.csv

myfile_V2.csv

myfile_V3.csv

myfile_V4.csv

myfile_V5.csv

....

The final concatenated file should be --> myfile_complete.csv

Any idea how do I proceed with this please in a way that I won't have to manually put the file names every time?

Re: How to import multiple files and concatenate them into one file

andreas_lds — Thu, 29 Sep 2022 11:20:10 GMT

Please have a look at https://stackoverflow.com/questions/60244/is-there-replacement-for-cat-on-windows

Or do you need the data in sas? If this is the case, please find of the numerous threads dealing with reading multiple files.Hint the infile-statement allows something like C:/mydir/myfiles/*.csv ...

Re: How to import multiple files and concatenate them into one file

MILKYLOVE — Thu, 29 Sep 2022 11:26:08 GMT

I am using Unix, the directory name was just an example. I guess it caused some confusions.

My issues is, I don't know how to concatenate all these files into one single file without having to manually input the name of each file every time. (maybe a loop?)

For a first step, I have tried to read all the files in the directory and list them:

filename myfiles '/sasapp/Liv_Marketing/delsquad/bloc/in';

data filenames (keep=filename);
     dir= dopen('myfiles');

     do file = 1 to dnum(dir);
          filename = dread(dir,file);
          output;
     end;

     rc= dclose(dir);
run;

This gives me a list of all the files present in the directory.

Now I need to import all of them and concatenate them into one output file.

Thanks for your help

Re: How to import multiple files and concatenate them into one file

PaigeMiller — Thu, 29 Sep 2022 11:31:54 GMT

Please pay attention to the hint from @andreas_lds , you don't need to specifically name each .csv file in your code. You don't even have to read the list of names in the folder.