[influxdb] v2: Fix history queries if items are not tagged (openhab#1…

…0888)

Was missing in openhab#10680

Fixes openhab#10887

Signed-off-by: Stefan Triller <github@stefantriller.de>
Signed-off-by: Luca Calcaterra <calcaterra.luca@gmail.com>

bundles/org.openhab.persistence.influxdb/src/main/java/org/openhab/persistence/influxdb/internal/influx2/InfluxDB2RepositoryImpl.java

@@ -194,6 +194,9 @@ private List<InfluxRow> convertClientResutToRepository(List<FluxTable> clientRes
     private Stream<InfluxRow> mapRawResultToHistoric(FluxTable rawRow) {
         return rawRow.getRecords().stream().map(r -> {
             String itemName = (String) r.getValueByKey(InfluxDBConstants.TAG_ITEM_NAME);
+            if (itemName == null) { // use measurement name if item is not tagged
+                itemName = r.getMeasurement();
+            }
             Object value = r.getValueByKey(COLUMN_VALUE_NAME_V2);
             Instant time = (Instant) r.getValueByKey(COLUMN_TIME_NAME_V2);
             return new InfluxRow(time, itemName, value);