Include 0 in a COUNT() in Hive - hive

Question

I have a table of users and medications and want to return the count of all meds by user even if the count is 0. The result would have columns for user, med, and count, and 9 users x 9 meds = 81 key rows.
user = ['1', '2', '3', '4', '5', '6', '7', '8', '9']
med = ['acyclovir' ,'azathioprine' ,'basiliximab' ,'bevacizumab' ,'carboplatin','ciprofloxacin_dexamethasone_otic' ,'cisplatin' ,'clofarabine', 'cyclophosphamide']
I tried:
SELECT user, med, COUNT(*)
FROM db.table
WHERE user IN ('1', '2', '3', '4', '5', '6', '7', '8', '9')
AND med IN ('acyclovir' ,'azathioprine' ,'basiliximab' ,'bevacizumab' ,'carboplatin','ciprofloxacin_dexamethasone_otic' ,'cisplatin' ,'clofarabine','cyclophosphamide')
GROUP BY user, med
ORDER BY user ASC
However, this only returned count for meds by user with COUNT(*) > 0. How can I change it to return all counts?

Answer 1

As far as I understand, you need to get a count of med given to a user, if none, then show 0.
Here is the qry you can use.
SELECT user,
SUM(case when med IN ('acyclovir' ,'azathioprine' ,'basiliximab' ,'bevacizumab' ,'carboplatin','ciprofloxacin_dexamethasone_otic' ,'cisplatin' ,'clofarabine','cyclophosphamide') then 1 else 0 end ) as med_count
--this will give you count of medicine taken by user. If 0 then the count will be 0. But its difficult to show the name of medicine.
FROM db.table
WHERE user IN ('1', '2', '3', '4', '5', '6', '7', '8', '9')
GROUP BY user
ORDER BY user ASC
Edit : could you please try this sql. It will give you med count of an user. If med isnt in the list it will show 0.
SELECT user,
SUM(case when med IN ('acyclovir' ,'azathioprine' ,'basiliximab' ,'bevacizumab' ,'carboplatin','ciprofloxacin_dexamethasone_otic' ,'cisplatin' ,'clofarabine','cyclophosphamide') then 1 else 0 end ) as med_count,
--this will give you count of medicine taken by user. If not in listed med then the count will be 0.
case when med IN ('acyclovir' ,'azathioprine' ,'basiliximab' ,'bevacizumab' ,'carboplatin','ciprofloxacin_dexamethasone_otic' ,'cisplatin' ,'clofarabine','cyclophosphamide') then med else null end as med
FROM db.table
WHERE user IN ('1', '2', '3', '4', '5', '6', '7', '8', '9')
GROUP BY user ,case when med IN ('acyclovir' ,'azathioprine' ,'basiliximab' ,'bevacizumab' ,'carboplatin','ciprofloxacin_dexamethasone_otic' ,'cisplatin' ,'clofarabine','cyclophosphamide') then med else null end
ORDER BY user ASC