Further Investigation
fragment("JSON_AGG(?)", e) instead of ("ARRAY_AGG(?)", e.id) would return you a Map with stringify keys.
I can’t somehow return the Schema within the fragment ?
Related articles:
It seems like other people have discussed this:
ecto-json-agg-for-structs
select-results-into-a-schema
Solution
Ben’s advice. Keep it simple. I did exactly what he suggested here is the solution:
def group_by_region do
results =
Location
|> Repo.all
|> Enum.group_by(fn(item) -> item.country_region end)
keys =
results |> Map.keys
Enum.map(keys, fn(key) ->
%{}
|> Map.put_new(:region, key)
|> Map.put_new(:count, length(Map.get(results, key)))
|> Map.put_new(:items, Map.get(results, key))
end)
end
