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From: Richard A. DeVenezia on 26 Jul 2010 15:44
On Jul 26, 5:27 am, m1st <lex.alt...(a)gmail.com> wrote:
> Hello!
>
> I'm trying to generate unique string identifier using md5() function
> from macro %sysfunc like:
> %let __hash = %nrbquote(%sysfunc(md5(%sysfunc(rand(UNIFORM)))));

Within the context of a single SAS session, you can also use MONOTONIC
to get a unique identifier
Monotonic never resets when called from the context of the macro
environment .

%let id = _%sysfunc(MONOTONIC());

When monotonic is used in the context of DATA Step or Proc SQL it
resets at the step boundary and sequence count is maintained per
invocation.

--
Richard A. DeVenezia
http://www.devenezia.com
From: m1st on 27 Jul 2010 02:22
On Jul 26, 5:24 pm, Patrick <patrick.mat...(a)gmx.ch> wrote:
> "Certainly, I can generate identifiers with data step, but as SAS
> does
> not allow to include one datastep into another, this would be an ugly
> solution. "
>
> So what do you need this MD5 values for. What do you want to achieve?
> What do you have and what do you need?

I need a macro which substitutes its call by some unique identifier,
so that:

data qwqwqw;
id = "%genRandomId(8)";
run;

becomes something like

data qwqwqw;
id = "A64F01D3";
run;

See why it's better to avoid using datasteps for ID generation?
From: 760105 on 27 Jul 2010 02:27

http://www.sascommunity.org/wiki/How_the_SAS_Random_Number_Generators_Work
From: m1st on 27 Jul 2010 02:27
On Jul 26, 6:49 pm, "data _null_;" <datan...(a)gmail.com> wrote:
> On Jul 26, 7:56 am, m1st <lex.alt...(a)gmail.com> wrote:
>
>
>
> > On Jul 26, 3:43 pm, "Richard A. DeVenezia" <rdevene...(a)gmail.com>
> > wrote:
>
> > > On Jul 26, 5:27 am, m1st <lex.alt...(a)gmail.com> wrote:
>
> > > > Hello!
>
> > > > I'm trying to generate unique string identifier using md5() function
> > > > from macro %sysfunc like:
> > > > %let __hash = %nrbquote(%sysfunc(md5(%sysfunc(rand(UNIFORM)))));
>
> > > > It takes md5 hash from a textual representation of a uniformly
> > > > distributed random number. However, I've encountered some problems
> > > > when quoting the output of md5. %nrbquote-ing is still unable to catch
> > > > all the special characters appearing in md5 output.
>
> > > > The questions are:
> > > > 1) How can I implement proper quoting in my case?
> > > > 2) Or, if you have suggestions on implementing the same thing without
> > > > md5, please share your mind.
>
> > > Try %QSYSFUNC
>
> > > --
> > > Richard A. DeVeneziahttp://www.devenezia.com
>
> > Actually, I tried it. No effect (more accurate, the same effect as the
> > mentioned %let).
> > It seems like SAS acquires macro quoting by mapping ASCII-codes of
> > special characters like % or & to some non-printable ASCII subset. The
> > fact is that MD5 returns a bit field, which is represented by 16
> > characters, not always printable, and sometimes they seem to collide
> > with SAS special quoting values.
> > Certainly, I can generate identifiers with data step, but as SAS does
> > not allow to include one datastep into another, this would be an ugly
> > solution.- Hide quoted text -
>
> > - Show quoted text -
>
> If you format the string could you still use it?
>
> 13   %let __hash = %qsysfunc(md5(%sysfunc(rand(UNIFORM))),hex16);
> 14
> 15   %put &__hash;
> 95C9FCF9CB0E4579

WOW! I missed this way of result formatting.
datanull, thanks a lot! The solution works like a charm!
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