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This PR collapses multiple queries fetching stats from a single table to a single query ```sql SELECT user_id as user_id, COUNT(CASE WHEN name = 'conversation_resolved' THEN 1 END) as resolved_count, AVG(CASE WHEN name = 'conversation_resolved' THEN value END) as avg_resolution_time, AVG(CASE WHEN name = 'first_response' THEN value END) as avg_first_response_time, AVG(CASE WHEN name = 'reply_time' THEN value END) as avg_reply_time FROM "reporting_events" WHERE "reporting_events"."account_id" = <account_id> AND "reporting_events"."created_at" >= '2025-09-14 18:30:00' AND "reporting_events"."created_at" < '2025-10-14 18:29:59' GROUP BY "reporting_events"."user_id"; ``` ### Why this works? Here's why this optimization is faster based on PostgreSQL internals: - Single Table Scan vs Multiple Scans: Earlier we did 4 sequential scans (or 4 index scans) of the same data, with the same where clause, now in a single scan all 4 `CASE` expressions are evaluated in a single pass. - Shared Buffer Cache Efficiency: PostgreSQL's shared buffer cache stores recently accessed pages, with this, pages are loaded once and re-used for all aggregation, earlier with separate queries we were forced to re-read all from the disk each time - Reduced planning and network overhead (4 vs 1 query) ### How is it tested 1. The specs all pass without making any changes 2. Verified the reports side by side after generating from report seeder #### How to test Generate seed data using the following command ```bash ACCOUNT_ID=1 ENABLE_ACCOUNT_SEEDING=true bundle exec rake db:seed:reports_data ``` Once done download the reports, checkout to this branch and download the reports again and compare them