Hello
Here is Hash code to select Last Row by group.
I want to ask-
Lets say there there is another data set called List_tbl and I want to select last row by group only for the groups in data set List_Tbl (So in this example I want to perform it only for groups 'A','C','D')
What is the way to tell SAS to perform it only for the groups in list_tbl?
Please note that in real life List_Tbl will have 200,000 groups and have table will have 5 millions groups.
data have;
input ID $ date : date9. var;
format date date9.;
cards;
A 01JAN2023 10
B 05JAN2023 5
B 06JAN2023 6
C 15JAN2023 7
C 16JAN2023 8
C 19JAN2023 9
C 20JAN2023 10
D 24JAN2023 2
;
Run;
Data List_tbl;
input ID $;
cards;
A
C
D
;
Run;
data _null_;
dcl hash H (dataset:'have',ordered: "a",duplicate:'r') ;
h.definekey ("id") ;
h.definedata ("id","date","var") ;/***Var to show in wanted data set**/
h.definedone () ;
h.output(dataset:'want');
stop;
retain _n_ _iorc_ ;
if 0 then do;
set have;
output;
end;
run;
How about that:
data have;
input ID $ date : date9. var;
format date date9.;
cards;
A 01JAN2023 10
B 05JAN2023 5
B 06JAN2023 6
C 15JAN2023 7
C 16JAN2023 8
C 19JAN2023 9
C 20JAN2023 10
D 24JAN2023 2
;
Run;
Data List_tbl;
input ID $;
cards;
A
C
D
;
Run;
/* sort have */
proc sort data = have;
by ID date;
Run;
data WANT;
/* use List_tbl as a dictionary */
dcl hash H (dataset:'List_tbl');
h.definekey ("id") ;
h.definedone () ;
do until(END);
set have end=END;
by ID;
/* check if it is the first row and is in the dictionary */
if first.ID AND H.find()=0 then output;
end;
stop;
run;
proc print data = WANT;
run;
?
Bart
How about that:
data have;
input ID $ date : date9. var;
format date date9.;
cards;
A 01JAN2023 10
B 05JAN2023 5
B 06JAN2023 6
C 15JAN2023 7
C 16JAN2023 8
C 19JAN2023 9
C 20JAN2023 10
D 24JAN2023 2
;
Run;
Data List_tbl;
input ID $;
cards;
A
C
D
;
Run;
/* sort have */
proc sort data = have;
by ID date;
Run;
data WANT;
/* use List_tbl as a dictionary */
dcl hash H (dataset:'List_tbl');
h.definekey ("id") ;
h.definedone () ;
do until(END);
set have end=END;
by ID;
/* check if it is the first row and is in the dictionary */
if first.ID AND H.find()=0 then output;
end;
stop;
run;
proc print data = WANT;
run;
?
Bart
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