Flagging multiple visits on the same date as 1

[doctortimi]

Hi SAS community,

I need help turning this logic into a program. I am trying to count the number of visits (with the variable Count) based on unique dates. This is what my data looks like.

Dataset

data dsn;
input PID $ Date  $ Place  Provider;
datalines;
001 10/10/2019 11 456
001 10/11/2019 11 400
001 10/11/2019 11 400
001 10/12/2019 11 509
;
run;

I would want an accumulating variable (Count) in my output like this;

PID Date Place Provider Count

001 10/10/2019 11 456 1

001 10/11/2019 11 400 2

001 10/11/2019 11 400 2

001 10/12/2019 11 509 3

Thank you.

[novinosrin · Accepted solution]

data want;
set dsn;
by pid Date;
retain count;
if first.pid then count=1;
else if first.date then count+1;
run;

[doctortimi]

Thank you!