SQL datasources: Consistent interval handling (#78517)

sql: apply the received interval-value

pkg/tsdb/sqleng/sql_engine.go

@@ -42,8 +42,6 @@ type SqlQueryResultTransformer interface {
 	GetConverterList() []sqlutil.StringConverter
 }
 
-var sqlIntervalCalculator = intervalv2.NewCalculator()
-
 type JsonData struct {
 	MaxOpenConns            int    `json:"maxOpenConns"`
 	MaxIdleConns            int    `json:"maxIdleConns"`
@@ -371,14 +369,10 @@ func (e *DataSourceHandler) executeQuery(query backend.DataQuery, wg *sync.WaitG
 
 // Interpolate provides global macros/substitutions for all sql datasources.
 var Interpolate = func(query backend.DataQuery, timeRange backend.TimeRange, timeInterval string, sql string) (string, error) {
-	minInterval, err := intervalv2.GetIntervalFrom(timeInterval, query.Interval.String(), query.Interval.Milliseconds(), time.Second*60)
-	if err != nil {
-		return "", err
-	}
-	interval := sqlIntervalCalculator.Calculate(timeRange, minInterval, query.MaxDataPoints)
+	interval := query.Interval
 
 	sql = strings.ReplaceAll(sql, "$__interval_ms", strconv.FormatInt(interval.Milliseconds(), 10))
-	sql = strings.ReplaceAll(sql, "$__interval", interval.Text)
+	sql = strings.ReplaceAll(sql, "$__interval", intervalv2.FormatDuration(interval))
 	sql = strings.ReplaceAll(sql, "$__unixEpochFrom()", fmt.Sprintf("%d", timeRange.From.UTC().Unix()))
 	sql = strings.ReplaceAll(sql, "$__unixEpochTo()", fmt.Sprintf("%d", timeRange.To.UTC().Unix()))