refactor(perf): user first heartbeats query

repositories/heartbeat.go

@@ -134,20 +134,22 @@ func (r *HeartbeatRepository) GetLatestByFilters(user *models.User, filterMap ma
 
 func (r *HeartbeatRepository) GetFirstByUsers() ([]*models.TimeByUser, error) {
 	var result []*models.TimeByUser
-	r.db.Model(&models.User{}).
-		Select(utils.QuoteSql(r.db, "users.id as %s, min(time) as %s", "user", "time")).
-		Joins("left join heartbeats on users.id = heartbeats.user_id").
-		Group("users.id").
+	r.db.Raw("with agg as (select " + utils.QuoteSql(r.db, "user_id, min(time) as %s", "time") + " from heartbeats group by user_id) " +
+		"select " + utils.QuoteSql(r.db, "id as %s, time ", "user") +
+		"from users " +
+		"left join agg on agg.user_id = id " +
+		"order by users.id").
 		Scan(&result)
 	return result, nil
 }
 
 func (r *HeartbeatRepository) GetLastByUsers() ([]*models.TimeByUser, error) {
 	var result []*models.TimeByUser
-	r.db.Model(&models.User{}).
-		Select(utils.QuoteSql(r.db, "users.id as %s, max(time) as %s", "user", "time")).
-		Joins("left join heartbeats on users.id = heartbeats.user_id").
-		Group("user").
+	r.db.Raw("with agg as (select " + utils.QuoteSql(r.db, "user_id, max(time) as %s", "time") + " from heartbeats group by user_id) " +
+		"select " + utils.QuoteSql(r.db, "id as %s, time ", "user") +
+		"from users " +
+		"left join agg on agg.user_id = id " +
+		"order by users.id").
 		Scan(&result)
 	return result, nil
 }

services/aggregation.go

@@ -68,14 +68,14 @@ func (srv *AggregationService) AggregateSummaries(userIds datastructure.Set[stri
 	slog.Info("generating summaries")
 
 	// Get a map from user ids to the time of their latest summary or nil if none exists yet
-	lastUserSummaryTimes, err := srv.summaryService.GetLatestByUser()
+	lastUserSummaryTimes, err := srv.summaryService.GetLatestByUser() // TODO: build user-specific variant of this query for efficiency
 	if err != nil {
 		config.Log().Error("error occurred", "error", err)
 		return err
 	}
 
 	// Get a map from user ids to the time of their earliest heartbeats or nil if none exists yet
-	firstUserHeartbeatTimes, err := srv.heartbeatService.GetFirstByUsers()
+	firstUserHeartbeatTimes, err := srv.heartbeatService.GetFirstByUsers() // TODO: build user-specific variant of this query for efficiency
 	if err != nil {
 		config.Log().Error("error occurred", "error", err)
 		return err