Postgresql – How to find similar (but different) names with the same soundex value

The condition:

AND    A.name = B.name 

only allows identical names, while you obviously want to match names with the same soundex value. So make that:

AND    soundex(A.name) = soundex(B.name)

If gid is the primary key, you can also simplify to:

GROUP BY a.gid, b.gid

However, since there obviously is no aggregation at all, you can simply remove the GROUP BY clause.

As suggested by PostGis, consider ST_DWithin() instead of ST_Distance() in the JOIN clause. The latter cannot utilize a spatial index.

If I understand you correctly, you are looking for a filtered (conditional) aggregate:

SELECT a.agent_id as agent_id, 
       COUNT(a.id) filter (where disposition = 'Completed Survey') as CompletedSurvey, 
       count(a.id) filter (where disposition = 'Partial Survey') as partial_survey
FROM forms a 
WHERE a.created_at >= '2015-08-01' 
  AND a.created_at <= '2015-08-31' 
GROUP BY a.agent_id;

Edit
for older versions (< 9.4) you need to use a case statement:

SELECT a.agent_id as agent_id, 
       COUNT(case when disposition = 'Completed Survey' then a.id end) as CompletedSurvey, 
       COUNT(case when disposition = 'Partial Survey' then a.id end) as partial_survey
FROM forms a 
WHERE a.created_at >= '2015-08-01' 
  AND a.created_at <= '2015-08-31' 
GROUP BY a.agent_id;