How do I subset/keep multiple rows based on value of another row

[pharaohjb]

I have a dataset that is set up as so:

Var1     Var2     Var3

1            A          1 January 2021

1            A          1 January 2021

1           A           5 January 2021

1            A          5 January 2021

1          B            31 Oct 2020

1           B            2 Nov 2020

My question is how can I ONLY keep the rows associated with the most recent values of Var2?  That is, I want all the rows associated with 5 Jan 2021 for Var2=A, and all the rows associated with 2 Nov 2020 for Var2=B, etc.

[novinosrin · Accepted solution]

A classic use-case for REMERGE and HAVING clause combine to subset-

proc sql;
  create table want as
  select *
  from have
  group by var1, var2
  having max(var3)=var3;
quit;

[pharaohjb]

Thank you!!

[Ksharp]

data have;
input Var1     Var2   $  Var3 $40.;
cards;
1            A          1 January 2021
1            A          1 January 2021
1           A           5 January 2021
1            A          5 January 2021
1          B            31 Oct 2020
1           B            2 Nov 2020
;
data want;
 do until(last.var3);
  set have;
  by var1 var2 var3 notsorted;
  if last.var2 then last=1;
 end;
 do until(last.var3);
  set have;
  by var1 var2 var3  notsorted;
  if last then output;
 end;
 drop last;
 run;