fix: address the first point increase without previous measurement va…

…lue (#7054)

pkg/query-service/app/metrics/v4/cumulative/timeseries.go

@@ -43,7 +43,7 @@ const (
 	increaseWithoutNegative = `If((per_series_value - lagInFrame(per_series_value, 1, 0) OVER rate_window) < 0, nan, If((ts - lagInFrame(ts, 1, toDate('1970-01-01')) OVER rate_window) >= 86400, nan, (per_series_value - lagInFrame(per_series_value, 1, 0) OVER rate_window)))`
 
 	experimentalRateWithoutNegative     = `If((per_series_value - lagInFrame(per_series_value, 1, 0) OVER rate_window) < 0, per_series_value, (per_series_value - lagInFrame(per_series_value, 1, 0) OVER rate_window) / (ts - lagInFrame(ts, 1, toDateTime(fromUnixTimestamp64Milli(%d))) OVER rate_window))`
-	experimentalIncreaseWithoutNegative = `If((per_series_value - lagInFrame(per_series_value, 1, 0) OVER rate_window) < 0, per_series_value, (per_series_value - lagInFrame(per_series_value, 1, 0) OVER rate_window))`
+	experimentalIncreaseWithoutNegative = `If((per_series_value - lagInFrame(per_series_value, 1, 0) OVER rate_window) < 0, per_series_value, ((per_series_value - lagInFrame(per_series_value, 1, 0) OVER rate_window) / (ts - lagInFrame(ts, 1, toDateTime(fromUnixTimestamp64Milli(%d))) OVER rate_window)) * (ts - lagInFrame(ts, 1, toDateTime(fromUnixTimestamp64Milli(%d))) OVER rate_window))`
 )
 
 // prepareTimeAggregationSubQueryTimeSeries prepares the sub-query to be used for temporal aggregation
@@ -167,7 +167,7 @@ func prepareTimeAggregationSubQuery(start, end, step int64, mq *v3.BuilderQuery)
 		innerSubQuery := fmt.Sprintf(queryTmpl, selectLabelsAny, step, op, timeSeriesSubQuery)
 		increaseExp := increaseWithoutNegative
 		if _, ok := os.LookupEnv("EXPERIMENTAL_INCREASE_WITHOUT_NEGATIVE"); ok {
-			increaseExp = experimentalIncreaseWithoutNegative
+			increaseExp = fmt.Sprintf(experimentalIncreaseWithoutNegative, start, start)
 		}
 		rateQueryTmpl :=
 			"SELECT %s ts, " + increaseExp +