topic Re: Comparing two SAS Programs in SAS Programming

Comparing two SAS Programs

AmitRathore — Thu, 02 Jul 2015 08:13:22 GMT

Dear Experts,

Is there any way to compare two SAS programs programatically. One way I know is to compare through TextPad but that is more of manually.

Br, Amit

Re: Comparing two SAS Programs

RW9 — Thu, 02 Jul 2015 09:02:30 GMT

Yes, just datastep load them into datasets, then proc compare:

data base;

length buffer $2000;

infile "xyz.sas";

input buffer $;

run;

...

proc compare base=base...;

run;

However, more importantly is why you want to do this. Computer comparisons are logical, hence if there is one extra line in at line 2, then everything from that point on will not match.

I would suggest that you are better off using version control software - its useful at any level of programming. This is a database which holds base file and every revision to that file. It can give you XML reports on differences etc. Also has roll-back functionality and never loses history.

Re: Comparing two SAS Programs

Kurt_Bremser — Thu, 02 Jul 2015 09:22:38 GMT

In UNIX, use the diff (diff utility - Wikipedia, the free encyclopedia) command. It was specifically written for this purpose.

Re: Comparing two SAS Programs

AmitRathore — Thu, 02 Jul 2015 11:49:01 GMT

The reason of comparing program is that I need to migrate some SAS programs from SDD3.5(windows) to SDD4.5(unix). And due to this I have to make same changes in the program like changes backward slash ('\') to forward slash ('/'). After making changes I need to make sure that anything else is not changed accidently.

Br,Amit

Re: Comparing two SAS Programs

RW9 — Thu, 02 Jul 2015 12:33:55 GMT

Well, you can use the compare above, but your better off using a text compare such as diff which KurtBremser has provided. You can then use that output as part of the documentation of the migration program.

Re: Comparing two SAS Programs

Ksharp — Thu, 02 Jul 2015 12:56:38 GMT

There are a couple of tools to compare two file . Like WinMerge

Re: Comparing two SAS Programs

WaltSmith — Thu, 02 Jul 2015 19:13:13 GMT

Also useful is the freely available tkdiff that gives a visual, side by side comparison of programs (Unix). On a Windows platform, the PSP editor has a very similar text difference tool that does a side by side comparison.

Re: Comparing two SAS Programs

sbb — Thu, 02 Jul 2015 21:25:40 GMT

The idea of comparing two SAS programs as-is could be flawed, depending on the SAS environment where invoked, and also considering if/how SAS AUTOCALL MACROs or MACRO statements (old SAS 79 style - ex: MACRO _BOO BLAH BLAH BLAH % ) may be exploited (that being embedded code references where you would only see %xxxxxxx; (disclaimer-invoked: oversimplified example) in the main SAS code-piece being analyzed.

Also depending on the SAS process / code complexity, there may be path-conditions influencing just how much of the code is executed, such as a passed SYSPARM or incoming %LET macro variables.

Scott Barry

SBBWorks, Inc.