Dashboard sql optimization

[ruebot]

We have a couple really slow queries on our dashboard that causes a very slow page load.

These two are the main culprits:

auk/app/helpers/dashboards_helper.rb

Lines 61 to 67 in bdd62ac

	def get_largest_collection
	largest_collection = WasapiFile.group(:user_id)
	.group(:collection_id)
	.sum(:size)
	.max_by { |_k, v| v }
	number_to_human_size(largest_collection[1])
	end

883.0ms: SELECT SUM("wasapi_files"."size") AS sum_size, "wasapi_files"."user_id" AS wasapi_files_user_id, "wasapi_files"."collection_id" AS wasapi_files_collection_id FROM "wasapi_files" GROUP BY "wasapi_files"."user_id", "wasapi_files"."collection_id";

---

auk/app/helpers/dashboards_helper.rb

Lines 77 to 79 in bdd62ac

	def get_total_number_of_warcs
	WasapiFile.distinct.count(:filename)
	end

22309.8ms: SELECT COUNT(DISTINCT "wasapi_files"."filename") FROM "wasapi_files";

[ruebot]

SELECT COUNT(*) FROM (SELECT DISTINCT "wasapi_files"."filename" FROM "wasapi_files") AS temp;

Takes the get_total_number_of_warcs query from ~22309.8ms to 1706.4ms