Creating a frequency table in Access VBA - ms-access

Question

I have a table where different participants are given multiple boxes of medicines on multiple days. I am trying to create a frequency table showing how much medicines have been distributed by the number of boxes to the participants.
The result I'm looking for is -
2 boxes = 1 (since only Lynda got a total of 2 boxes), 4 boxes = 2 (since Ryan and Rinky both got a total of 4 boxes after adding up the medicine boxes)
Please let me know what approach would be the best in this case.
Thanks for your help.
-Nams

Answer 1

I think you want:
SELECT t.SumOf, Count(t.[PARTICIPANT ID]) AS CountOf
FROM (SELECT Table1.[PARTICIPANT ID], Sum(Table1.MEDICINE_BOX) AS SumOf
FROM Table1
GROUP BY Table1.[PARTICIPANT ID]) AS t
GROUP BY t.SumOf;
Where table1 is the name of your table.

Answer 2

If your table is like this:
medicine_dispense
participantID date amount_boxes
ABC 8/29/12 1
ABC 8/30/12 2
XYZ 8/29/12 1
XYZ 8/30/12 1
then a query like this:
select
amount_boxes, count(participantID)
from
medicine_dispense
should work

Answer 3

I'll use generic SQL. You can paste SQL into Access queries in SQL view. (You might have to delete the CHECK() constraint.)
create table participant_meds (
participant varchar(10) not null,
distribution_date date not null default current_date,
num_boxes integer not null check (num_boxes > 0),
primary key (participant, distribution_date)
);
insert into participant_meds values ('Ryan', '2012-02-03', 1);
insert into participant_meds values ('Ryan', '2012-06-07', 3);
insert into participant_meds values ('Rinky', '2012-02-28', 4);
insert into participant_meds values ('Lynda', '2012-03-04', 2);
insert into participant_meds values ('Russ', '2012-04-05', 2);
insert into participant_meds values ('Russ', '2012-05-08', 2);
insert into participant_meds values ('Russ', '2012-06-12', 2);
Resulting data, sorted, for copy/paste.
participant distribution_date num_boxes
Lynda 2012-03-04 2
Rinky 2012-02-28 4
Russ 2012-04-05 2
Russ 2012-05-08 2
Russ 2012-06-12 2
Ryan 2012-02-03 1
Ryan 2012-06-07 3
This query gives you the total boxes per participant.
select sum(num_boxes) boxes, participant
from participant_meds
group by participant;
6;"Russ"
2;"Lynda"
4;"Ryan"
4;"Rinky"
Use that query in the FROM clause as if it were a table. (I'd consider storing that query as a view, because I suspect that the total number of boxes per participant might be useful. Also, Access has historically been good at optimizing queries that use views.)
select boxes num_boxes, count(participant) num_participants
from (select sum(num_boxes) boxes, participant
from participant_meds
group by participant) total_boxes
group by num_boxes
order by num_boxes;
num_boxes num_participants
--
2 1
4 2
6 1