Select multiple counts from one database table in one sql command access - sql

Question

I have a single table in the following format:
STATE SURVEY_ANSWER
NC high
NC moderate
WA high
FL low
NC high
I am looking for a single query that will get me the following result:
STATE HIGH MODERATE LOW
NC 2 1 0
WA 1 0 0
FL 0 0 1
Unfortunately, these are the results I am getting:
STATE HIGH MODERATE LOW
NC 3 1 1
WA 3 1 1
FL 3 1 1
Here is the code I am using:
Select mytable.STATE,
(SELECT COUNT(*) FROM mytable WHERE mytable.survey_answer = 'low' and state = mytable.state) AS low,
(SELECT COUNT(*) FROM mytable WHERE mytable.survey_answer = 'moderate' and state = mytable.state) AS moderate,
(SELECT COUNT(*) FROM mytable WHERE mytable.survey_answer = 'high' and state = mytable.state) AS high,
FROM mytable
GROUP BY mytable.state;
While this and other forums have been very helpful I am unable to figure out what I am doing wrong. PLEASE NOTE: I am using Access so CASE WHEN solutions do not work. Thank you for any advice.

Answer 1

It looks like this may be an issue caused by not using table aliases. Because you are doing sub-queries on the same table that the outer SELECT is using and not giving the outer table an alias, both of the conditions in the WHERE of the sub-query are only using data in the sub-query.
In other words, when you write:
SELECT COUNT(*) FROM mytable WHERE mytable.survey_answer = 'low' and state = mytable.state
It doesn't know anything about the outer query.
Try this:
SELECT t1.STATE,
(SELECT COUNT(*) FROM mytable t2 WHERE t2.state = t1.state AND t2.survey_answer = 'low') low,
(SELECT COUNT(*) FROM mytable t3 WHERE t3.state = t1.state AND t3.survey_answer = 'moderate') moderate,
(SELECT COUNT(*) FROM mytable t4 WHERE t4.state = t1.state AND t4.survey_answer = 'high') high,
FROM mytable t1
GROUP BY t1.state

Answer 2

Aiias answer explains why your current query is not working, but I thought I'd point out that your assumption that you can't use CASE WHEN solutions is only partly right, yes you can't use CASE WHEN but that doesn't mean you need correlated subqueries. You could simply use:
SELECT mytable.STATE,
SUM(IIF(mytable.survey_answer = 'low', 1, 0) AS low,
SUM(IIF(mytable.survey_answer = 'moderate', 1, 0) AS moderate,
SUM(IIF(mytable.survey_answer = 'high', 1, 0) AS high
FROM mytable
GROUP BY mytable.state;