SAS - Row by row Comparison within different ID Variables of Same Dataset and delete ALL Duplicates

I need some help in trying to execute a comparison of rows within different ID variable groups, all in a single dataset.

That is, if there is any duplicate observation within two or more ID groups, then I'd like to delete the observation entirely.

I want to identify any duplicates between rows of different groups and delete the observation entirely.

For example:

The output I desire is:

ID  Value
 1    D
 3    Z

I have looked online extensively, and tried a few things. I thought I could mark the duplicates with a flag and then delete based off that flag.

The flagging code is:

data have;
set want;
flag = first.ID ne last.ID;
run;

This worked for some cases, but I also got duplicates within the same value group flagged.

Therefore the first observation got deleted:

ID  Value
 3    Z

I also tried:

data have;
set want;
flag = first.ID ne last.ID and first.value ne last.value;
run;

but that didn't mark any duplicates at all.

I would appreciate any help. Please let me know if any other information is required.

Thanks.

Solution

Here's a fairly simple way to do it: sort and deduplicate by value + ID, then keep only rows with values that occur only for a single ID.

data have;
input ID  Value $;
cards;
 1    A
 1    B
 1    C
 1    D
 1    D
 2    A
 2    C
 3    A
 3    Z
 3    B
 ;
run;

proc sort data = have nodupkey;
    by value ID;
run;

data want;
set have;
by value;
if first.value and last.value;
run;

proc sql version:

proc sql;
create table want as
select distinct ID, value from have
group by value
having count(distinct id) =1
order by id
;
quit;