SAS lowercase SHA256 string - sas

Question

Currently testing a SHA256 function in order to prepare a variable for use in another application.
The user has requested the SHA256 result be in lower case. I created a quick record in order to make sure I can convert the string-
data have;
input first $ last $ dob $ 10. sex $;
cards;
test person 1955-07-31 1
;
run;
Seems it will not allow a lower case string once passed through the SHA function.
Is there a workaround for this? The below attempt did not yield desirable results.
data have2;
set have;
source = catt(first,last,dob,sex);
encryp = lowcase(sha256(source));
format encryp $hex64.;
run;

Answer 1

The issue is not with the sha256 function, but with the $HEX64 format.
When you used lowcase you actually do some harm to the SHA256 result: you're not altering the hexadecimal representation, but you're actually altering the characters themselves, which means your result isn't accurate - and then you're displaying them with $HEX64. which will always show capital letters for the hexadecimal characters.
What instead you want, presumably, is to store the lower case version of the $HEX64. format. You can do that with put:
data want;
set have;
source = catt(first,last,dob,sex);
encryp = sha256(source);
lower = lowcase(put(encryp,$HEX64.));
run;
Note what encryp looks like - something totally different, and probably not particularly useful. You can of course skip that step if you want.

Answer 2

Below will do it using a put statement with the format inside:
data have2;
set have;
encryp = lowcase(put(sha256(catt(first,last,dob,sex)),$hex64.));
run;
It will show an entirely different encryption code compared to your method but it remains consistent.
data have;
input first $ last $ dob $ 10. sex $;
cards;
test person 1955-07-31 1
test person 1955-07-31 1
test2 person 1977-08-11 2
test3 person 1945-12-22 1
;
run;
data have2;
set have;
new_encryp = lowcase(put(sha256(catt(first,last,dob,sex)),hex64.)); /* new method */
encryp = lowcase(sha256(catt(first,last,dob,sex))); /* what you tried */
format encryp $hex64.;
run;
/* output */
first last dob sex new_encryp encryp
test person 7/31/1955 1 038a855a47f40edf54094adc4366e3e79c1a931346d7968e96d2cb930b01e7bc 039A857A67F40EDF74096AFC6366E3E79C1A931366D7969E96F2EB930B01E7BC
test person 7/31/1955 1 038a855a47f40edf54094adc4366e3e79c1a931346d7968e96d2cb930b01e7bc 039A857A67F40EDF74096AFC6366E3E79C1A931366D7969E96F2EB930B01E7BC
test2 person 8/11/1977 2 1117ab614f48a7edfbe9d615f12acad9d564b457b0f31bb2619f7eb9b10f1e58 1117AB616F68A7EDFBE9F615F12AEAF9F564B477B0F31BB261FF7EB9B10F1E78
test3 person 12/22/1945 1 d1cb00ebe044c0553039f99592dc7bd4804eac2c13da8208fd82459c3a37efd1 F1EB00EBE064E0753039F99592FC7BF4806EAC2C13FA8208FD82659C3A37EFF1

Answer 3

*convert case;
%let txt="SEQ_CLAIM_ID, SEQ_MEMB_ID, EFFECTIVE_DATE";
%macro lower_case(txt);
data;
text=lowcase(&txt);
run;
%mend;
%lower_case(&txt);