Meter

src/main/angular/src/app/app.html

@@ -16,4 +16,6 @@
   </div>
 </div>
 
+<div class="bodyContent">
   <router-outlet/>
+</div>

src/main/angular/src/app/app.less

@@ -1,7 +1,6 @@
 @sidebarColor: #62b0ca;
 
 .sidebar {
-  margin-left: -2em;
   position: fixed;
   display: flex;
   height: 100%;
@@ -49,3 +48,7 @@
   }
 
 }
+
+.bodyContent {
+  margin-left: 2em;
+}

src/main/angular/src/app/plot/plot/plot.component.ts

@@ -8,13 +8,15 @@ import {NTU, UTN} from '../../COMMON';
 import {Graph} from '../axis/graph/Graph';
 import {Axis} from '../axis/Axis';
 import {Subscription} from 'rxjs';
-import {Delta, DeltaService} from '../../series/delta/delta-service';
+import {DeltaService} from '../../series/delta/delta-service';
-import {Bool, BoolService} from '../../series/bool/bool-service';
+import {BoolService} from '../../series/bool/bool-service';
 import {VaryingService} from '../../series/varying/varying-service';
 import {Interval} from '../../series/Interval';
 import {SeriesService} from '../../series/series.service';
 import {GraphType} from '../axis/graph/GraphType';
 import {Varying} from '../../series/varying/Varying';
+import {Delta} from '../../series/delta/Delta';
+import {Bool} from '../../series/bool/Bool';
 
 type Dataset = ChartDataset<any, any>[][number];
 

src/main/angular/src/app/series/MinMaxAvg.ts

@@ -49,7 +49,7 @@ export function toDelta(points: number[][], factor: number): Point[] {
   for (const p of points) {
     result.push({
       x: p[0] * 1000,
-      y: (p[2] - p[1]) * factor,
+      y: (p[1]) * factor,
     });
   }
   return result;

src/main/angular/src/app/series/bool/Bool.ts

@@ -0,0 +1,26 @@
+import {Series} from "../Series";
+import {validateBoolean, validateDate} from "../../COMMON";
+
+export class Bool {
+
+  constructor(
+    readonly series: Series,
+    readonly date: Date,
+    readonly end: Date,
+    readonly state: boolean,
+    readonly terminated: boolean,
+  ) {
+    //
+  }
+
+  static fromJson(json: any): Bool {
+    return new Bool(
+      Series.fromJson(json.series),
+      validateDate(json.date),
+      validateDate(json.end),
+      validateBoolean(json.state),
+      validateBoolean(json.terminated),
+    );
+  }
+
+}

src/main/angular/src/app/series/bool/bool-service.ts

@@ -1,30 +1,6 @@
 import {Injectable} from '@angular/core';
-import {ApiService, CrudService, validateBoolean, validateDate} from '../../COMMON';
+import {ApiService, CrudService} from '../../COMMON';
-import {Series} from '../Series';
+import {Bool} from './Bool';
-
-export class Bool {
-
-  constructor(
-    readonly series: Series,
-    readonly date: Date,
-    readonly end: Date,
-    readonly state: boolean,
-    readonly terminated: boolean,
-  ) {
-    //
-  }
-
-  static fromJson(json: any): Bool {
-    return new Bool(
-      Series.fromJson(json.series),
-      validateDate(json.date),
-      validateDate(json.end),
-      validateBoolean(json.state),
-      validateBoolean(json.terminated),
-    );
-  }
-
-}
 
 @Injectable({
   providedIn: 'root'

src/main/angular/src/app/series/delta/Delta.ts

@@ -0,0 +1,24 @@
+import {validateDate, validateNumber} from "../../COMMON";
+import {Meter} from './meter/Meter';
+
+export class Delta {
+
+  constructor(
+    readonly meter: Meter,
+    readonly date: Date,
+    readonly first: number,
+    readonly last: number,
+  ) {
+    //
+  }
+
+  static fromJson(json: any): Delta {
+    return new Delta(
+      Meter.fromJson(json.meter),
+      validateDate(json.date),
+      validateNumber(json.first),
+      validateNumber(json.last),
+    );
+  }
+
+}

src/main/angular/src/app/series/delta/delta-service.ts

@@ -1,28 +1,6 @@
 import {Injectable} from '@angular/core';
-import {ApiService, CrudService, validateDate, validateNumber} from '../../COMMON';
+import {ApiService, CrudService} from '../../COMMON';
-import {Series} from '../Series';
+import {Delta} from './Delta';
-
-export class Delta {
-
-  constructor(
-    readonly series: Series,
-    readonly date: Date,
-    readonly first: number,
-    readonly last: number,
-  ) {
-    //
-  }
-
-  static fromJson(json: any): Delta {
-    return new Delta(
-      Series.fromJson(json.series),
-      validateDate(json.date),
-      validateNumber(json.first),
-      validateNumber(json.last),
-    );
-  }
-
-}
 
 @Injectable({
   providedIn: 'root'

src/main/angular/src/app/series/delta/meter/Meter.ts

@@ -0,0 +1,24 @@
+import {Series} from "../../Series";
+import {validateDate, validateNumber, validateString} from "../../../COMMON";
+
+export class Meter {
+
+  constructor(
+    readonly id: number,
+    readonly series: Series,
+    readonly number: string,
+    readonly first: Date,
+  ) {
+    //
+  }
+
+  static fromJson(json: any): Meter {
+    return new Meter(
+      validateNumber(json.id),
+      Series.fromJson(json.series),
+      validateString(json.number),
+      validateDate(json.first),
+    );
+  }
+
+}

src/main/angular/src/app/topic/Topic.ts

@@ -17,6 +17,8 @@ export class Topic {
     readonly timestampType: TimestampType,
     readonly timestampQuery: string,
     readonly timestampLast: Date | null,
+    readonly meterNumberQuery: string,
+    readonly meterNumberLast: string,
     readonly queries: TopicQuery[],
     readonly payload: string,
     readonly error: string,
@@ -35,6 +37,8 @@ export class Topic {
       validateString(json.timestampType) as TimestampType,
       validateString(json.timestampQuery),
       mapNotNull(json.timestampLast, validateDate),
+      validateString(json.meterNumberQuery),
+      validateString(json.meterNumberLast),
       validateList(json.queries, TopicQuery.fromJson),
       validateString(json.payload),
       validateString(json.error),

src/main/angular/src/app/topic/list/topic-list.component.html

@@ -1,3 +1,8 @@
+<div class="options">
+  <label><input type="checkbox" [(ngModel)]="config.topicList.unused">Ungenutzte</label>
+  <label><input type="checkbox" [(ngModel)]="config.topicList.used">Genutzte</label>
+</div>
+
 <table class="TopicList">
   @for (topic of sorted(); track topic.id) {
     <tr class="head">
@@ -10,6 +15,14 @@
       <td class="timestampType" [class.empty]="topic.timestampType === null">{{ topic.timestampType }}</td>
       <td class="timestampLast" [class.empty]="topic.timestampLast === null" colspan="6">{{ topic.timestampLast | date:'long':'':'de-DE' }}</td>
     </tr>
+    @if (topic.queries[0]?.series?.type === SeriesType.DELTA) {
+      <tr class="meter">
+        <td class="meterNumberQuery" [class.empty]="!topic.meterNumberQuery">{{ topic.meterNumberQuery }}</td>
+        <td class="meterNumberLast" [class.empty]="topic.meterNumberLast === null"></td>
+        <td class="meterNumberLast" [class.empty]="topic.meterNumberLast === null" colspan="5">{{ topic.meterNumberLast }}</td>
+        <td class="meterNumberLast" [class.empty]="topic.timestampLast === null">{{ topic.timestampLast | date:'long':'':'de-DE' }}</td>
+      </tr>
+    }
     @for (query of topic.queries; track $index) {
       <tr class="query">
         <td class="valueQuery" [class.empty]="query.valueQuery === null">{{ query.valueQuery }}</td>

src/main/angular/src/app/topic/list/topic-list.component.less

@@ -22,6 +22,10 @@ table.TopicList {
     background-color: darkseagreen;
   }
 
+  tr.meter {
+    background-color: #ffe7bd;
+  }
+
   tr.spacer {
     th, td {
       border: none;
@@ -53,7 +57,11 @@ table.TopicList {
   }
 
   .timestampLast {
+    text-align: right;
+  }
 
+  .meterNumberLast {
+    text-align: right;
   }
 
   .valueQuery {

src/main/angular/src/app/topic/list/topic-list.component.ts

@@ -11,6 +11,7 @@ import {SeriesService} from '../../series/series.service';
 import {Config} from '../../config/Config';
 import {ageString} from '../../COMMON';
 import {ConfigService} from '../../config/config.service';
+import {SeriesType} from '../../series/SeriesType';
 
 @Component({
   selector: 'app-topic-list',
@@ -25,6 +26,8 @@ export class TopicListComponent implements OnInit, OnDestroy {
 
   protected readonly ageString = ageString;
 
+  protected readonly SeriesType = SeriesType;
+
   protected now: Date = new Date();
 
   protected topicList: Topic[] = [];
@@ -55,10 +58,6 @@ export class TopicListComponent implements OnInit, OnDestroy {
     this.subs.forEach(sub => sub.unsubscribe());
   }
 
-  sorted() {
-    return this.topicList.filter(this.filter).sort(this.compare);
-  }
-
   private readonly update = (topic: Topic) => {
     const index = this.topicList.findIndex(t => t.id === topic.id);
     if (index >= 0) {
@@ -68,6 +67,10 @@ export class TopicListComponent implements OnInit, OnDestroy {
     }
   };
 
+  sorted() {
+    return this.topicList.filter(this.filter).sort(this.compare);
+  }
+
   private readonly filter = (topic: Topic) => {
     return ((!topic.used && this.config.topicList.unused) || (topic.used && this.config.topicList.used));
   }

src/main/angular/src/styles.less

@@ -5,7 +5,6 @@ html, body {
 
 body {
   font-family: sans-serif;
-  margin-left: 2em;
 }
 
 table {
@@ -23,7 +22,7 @@ input, select, textarea {
   font-size: inherit;
 }
 
-input, select {
+input:not([type=checkbox]), select {
   width: 100%;
   margin: 0;
   outline: none;

src/main/java/de/ph87/data/DemoService.java

@@ -62,8 +62,9 @@ public class DemoService {
 
     final Series electricityEnergyProduce = series("electricity/energy/produce", "kWh", SeriesType.DELTA, 5);
     final Series electricityPowerProduce = series("electricity/power/produce", "W", SeriesType.VARYING, 5);
-    topic(
+    topicMeterNumber(
       "openDTU/pv/patrix/json2",
+      "$.inverter",
       new TopicQuery(electricityEnergyProduce, "$.totalKWh"),
       new TopicQuery(electricityPowerProduce, "$.totalW")
     );
@@ -72,8 +73,9 @@ public class DemoService {
     final Series electricityPowerPurchase = series("electricity/power/purchase", "W", SeriesType.VARYING, 5);
     final Series electricityEnergyDelivery = series("electricity/energy/delivery", "kWh", SeriesType.DELTA, 5);
     final Series electricityPowerDelivery = series("electricity/power/delivery", "W", SeriesType.VARYING, 5);
-    topic(
+    topicMeterNumber(
       "electricity/grid/json",
+      "\"1ZPA0020300305\"",
       new TopicQuery(electricityEnergyPurchase, "$.purchaseWh", 0.001),
       new TopicQuery(electricityPowerPurchase, "$.powerW", TopicQueryFunction.ONLY_POSITIVE),
       new TopicQuery(electricityEnergyDelivery, "$.deliveryWh", 0.001),
@@ -220,4 +222,12 @@ public class DemoService {
     topic.getQueries().addAll(List.of(queries));
   }
 
+  private void topicMeterNumber(@NonNull final String name, @NonNull final String meterNumberQuery, @NonNull final TopicQuery... queries) {
+    final Topic topic = topicRepository.findByName(name).orElseGet(() -> topicRepository.save(new Topic(name)));
+    topic.setMeterNumberQuery(meterNumberQuery);
+    topic.setTimestampQuery("$.timestamp");
+    topic.getQueries().clear();
+    topic.getQueries().addAll(List.of(queries));
+  }
+
 }

src/main/java/de/ph87/data/series/data/delta/Delta.java

@@ -1,6 +1,5 @@
 package de.ph87.data.series.data.delta;
 
-import de.ph87.data.series.data.DataId;
 import jakarta.persistence.Column;
 import jakarta.persistence.Entity;
 import jakarta.persistence.Id;
@@ -19,7 +18,7 @@ public abstract class Delta {
 
   @Id
   @NonNull
-  private DataId id;
+  private DeltaId id;
 
   @Version
   private long version;
@@ -31,7 +30,7 @@ public abstract class Delta {
   @Column(nullable = false)
   private double last;
 
-  protected Delta(@NonNull final DataId id, final double value) {
+  protected Delta(@NonNull final DeltaId id, final double value) {
     this.id = id;
     this.first = value;
     this.last = value;
@@ -47,7 +46,7 @@ public abstract class Delta {
   @Entity(name = "DeltaFive")
   public static class Five extends Delta {
 
-    public Five(@NonNull final DataId id, @NonNull final double value) {
+    public Five(@NonNull final DeltaId id, @NonNull final double value) {
       super(id, value);
     }
 
@@ -59,7 +58,7 @@ public abstract class Delta {
   @Entity(name = "DeltaHour")
   public static class Hour extends Delta {
 
-    public Hour(@NonNull final DataId id, @NonNull final double value) {
+    public Hour(@NonNull final DeltaId id, @NonNull final double value) {
       super(id, value);
     }
 
@@ -71,7 +70,7 @@ public abstract class Delta {
   @Entity(name = "DeltaDay")
   public static class Day extends Delta {
 
-    public Day(@NonNull final DataId id, @NonNull final double value) {
+    public Day(@NonNull final DeltaId id, @NonNull final double value) {
       super(id, value);
     }
 
@@ -83,7 +82,7 @@ public abstract class Delta {
   @Entity(name = "DeltaWeek")
   public static class Week extends Delta {
 
-    public Week(@NonNull final DataId id, @NonNull final double value) {
+    public Week(@NonNull final DeltaId id, @NonNull final double value) {
       super(id, value);
     }
 
@@ -95,7 +94,7 @@ public abstract class Delta {
   @Entity(name = "DeltaMonth")
   public static class Month extends Delta {
 
-    public Month(@NonNull final DataId id, @NonNull final double value) {
+    public Month(@NonNull final DeltaId id, @NonNull final double value) {
       super(id, value);
     }
 
@@ -107,7 +106,7 @@ public abstract class Delta {
   @Entity(name = "DeltaYear")
   public static class Year extends Delta {
 
-    public Year(@NonNull final DataId id, @NonNull final double value) {
+    public Year(@NonNull final DeltaId id, @NonNull final double value) {
       super(id, value);
     }
 

src/main/java/de/ph87/data/series/data/delta/DeltaDto.java

@@ -1,7 +1,7 @@
 package de.ph87.data.series.data.delta;
 
-import de.ph87.data.series.SeriesDto;
 import de.ph87.data.series.data.Interval;
+import de.ph87.data.series.data.delta.meter.MeterDto;
 import de.ph87.data.websocket.IWebsocketMessage;
 import lombok.Data;
 import lombok.Getter;
@@ -14,21 +14,20 @@ import java.time.ZonedDateTime;
 public abstract class DeltaDto implements IWebsocketMessage {
 
   @NonNull
-  private SeriesDto series;
+  private MeterDto meter;
 
   @NonNull
   private ZonedDateTime date;
 
   public final double first;
 
-  @NonNull
   public final double last;
 
   @NonNull
   public final Interval interval;
 
   protected DeltaDto(@NonNull final Delta delta, @NonNull final Interval interval) {
-    this.series = new SeriesDto(delta.getId().getSeries(), false);
+    this.meter = new MeterDto(delta.getId().getMeter());
     this.date = delta.getId().getDate();
     this.first = delta.getFirst();
     this.last = delta.getLast();
@@ -38,7 +37,7 @@ public abstract class DeltaDto implements IWebsocketMessage {
   @NonNull
   @Override
   public String getWebsocketTopic() {
-    return "Delta/%d/%s".formatted(series.id, interval);
+    return "Delta/%d/%s".formatted(meter.series.id, interval);
   }
 
   @Getter

src/main/java/de/ph87/data/series/data/delta/DeltaId.java

@@ -0,0 +1,36 @@
+package de.ph87.data.series.data.delta;
+
+import de.ph87.data.series.data.Interval;
+import de.ph87.data.series.data.delta.meter.Meter;
+import jakarta.persistence.Column;
+import jakarta.persistence.Embeddable;
+import jakarta.persistence.ManyToOne;
+import lombok.EqualsAndHashCode;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.NonNull;
+import lombok.ToString;
+
+import java.time.ZonedDateTime;
+
+@Getter
+@ToString
+@Embeddable
+@EqualsAndHashCode
+@NoArgsConstructor
+public class DeltaId {
+
+  @NonNull
+  @ManyToOne(optional = false)
+  private Meter meter;
+
+  @NonNull
+  @Column(nullable = false)
+  private ZonedDateTime date;
+
+  public DeltaId(@NonNull final Meter meter, @NonNull final ZonedDateTime date, @NonNull final Interval interval) {
+    this.meter = meter;
+    this.date = interval.align.apply(date);
+  }
+
+}

src/main/java/de/ph87/data/series/data/delta/DeltaPoint.java

@@ -10,23 +10,20 @@ import java.time.ZonedDateTime;
 @SuppressWarnings("unused") // used by repository query
 public class DeltaPoint implements SeriesPoint {
 
+  @NonNull
   public final ZonedDateTime date;
 
-  public final double first;
+  public final double delta;
 
-  public final double last;
+  public DeltaPoint(@NonNull final ZonedDateTime date, final double delta) {
-
+    this.date = date;
-  public DeltaPoint(@NonNull final Delta delta) {
+    this.delta = delta;
-    this.date = delta.getId().getDate();
-    this.first = delta.getFirst();
-    this.last = delta.getLast();
   }
 
   @Override
   public void toJson(final JsonGenerator jsonGenerator) throws IOException {
     jsonGenerator.writeNumber(date.toEpochSecond());
-    jsonGenerator.writeNumber(first);
+    jsonGenerator.writeNumber(delta);
-    jsonGenerator.writeNumber(last);
   }
 
 }

src/main/java/de/ph87/data/series/data/delta/DeltaRepo.java

@@ -1,7 +1,6 @@
 package de.ph87.data.series.data.delta;
 
 import de.ph87.data.series.Series;
-import de.ph87.data.series.data.DataId;
 import lombok.NonNull;
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.data.repository.CrudRepository;
@@ -11,10 +10,10 @@ import java.time.ZonedDateTime;
 import java.util.List;
 
 @NoRepositoryBean
-public interface DeltaRepo<T extends Delta> extends CrudRepository<T, DataId> {
+public interface DeltaRepo<T extends Delta> extends CrudRepository<T, DeltaId> {
 
   @NonNull
-  @Query("select new de.ph87.data.series.data.delta.DeltaPoint(e) from #{#entityName} e where e.id.series = :series and e.id.date >= :first and e.id.date < :after")
+  @Query("select new de.ph87.data.series.data.delta.DeltaPoint(e.id.date, sum(e.last - e.first)) from #{#entityName} e where e.id.meter.series = :series and e.id.date >= :first and e.id.date < :after group by e.id.date")
   List<DeltaPoint> points(@NonNull Series series, @NonNull ZonedDateTime first, @NonNull ZonedDateTime after);
 
 }

src/main/java/de/ph87/data/series/data/delta/DeltaService.java

@@ -2,8 +2,9 @@ package de.ph87.data.series.data.delta;
 
 import de.ph87.data.series.ISeriesPointRequest;
 import de.ph87.data.series.Series;
-import de.ph87.data.series.data.DataId;
 import de.ph87.data.series.data.Interval;
+import de.ph87.data.series.data.delta.meter.Meter;
+import de.ph87.data.series.data.delta.meter.MeterService;
 import lombok.NonNull;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
@@ -34,18 +35,21 @@ public class DeltaService {
 
   private final ApplicationEventPublisher applicationEventPublisher;
 
+  private final MeterService meterService;
+
   @Transactional
-  public void write(@NonNull final Series series, @NonNull final ZonedDateTime date, final double value) {
+  public void write(@NonNull final Series series, @NonNull final String meterNumber, @NonNull final ZonedDateTime date, final double value) {
-    write(series, five, Interval.FIVE, date, value, Delta.Five::new, DeltaDto.Five::new);
+    final Meter meter = meterService.getLastValidBySeriesAndNumberOrCreate(series, meterNumber, date);
-    write(series, hour, Interval.HOUR, date, value, Delta.Hour::new, DeltaDto.Hour::new);
+    write(meter, five, Interval.FIVE, date, value, Delta.Five::new, DeltaDto.Five::new);
-    write(series, day, Interval.DAY, date, value, Delta.Day::new, DeltaDto.Day::new);
+    write(meter, hour, Interval.HOUR, date, value, Delta.Hour::new, DeltaDto.Hour::new);
-    write(series, week, Interval.WEEK, date, value, Delta.Week::new, DeltaDto.Week::new);
+    write(meter, day, Interval.DAY, date, value, Delta.Day::new, DeltaDto.Day::new);
-    write(series, month, Interval.MONTH, date, value, Delta.Month::new, DeltaDto.Month::new);
+    write(meter, week, Interval.WEEK, date, value, Delta.Week::new, DeltaDto.Week::new);
-    write(series, year, Interval.YEAR, date, value, Delta.Year::new, DeltaDto.Year::new);
+    write(meter, month, Interval.MONTH, date, value, Delta.Month::new, DeltaDto.Month::new);
+    write(meter, year, Interval.YEAR, date, value, Delta.Year::new, DeltaDto.Year::new);
   }
 
-  private <DELTA extends Delta, DTO extends DeltaDto> void write(@NonNull final Series series, @NonNull final DeltaRepo<DELTA> repo, @NonNull final Interval interval, @NonNull final ZonedDateTime date, final double value, @NonNull final BiFunction<DataId, Double, DELTA> create, @NonNull final BiFunction<DELTA, Interval, DTO> toDto) {
+  private <DELTA extends Delta, DTO extends DeltaDto> void write(@NonNull final Meter meter, @NonNull final DeltaRepo<DELTA> repo, @NonNull final Interval interval, @NonNull final ZonedDateTime date, final double value, @NonNull final BiFunction<DeltaId, Double, DELTA> create, @NonNull final BiFunction<DELTA, Interval, DTO> toDto) {
-    final DataId id = new DataId(series, date, interval);
+    final DeltaId id = new DeltaId(meter, date, interval);
     final DELTA delta = repo.findById(id).stream().peek(existing -> existing.update(value)).findFirst().orElseGet(() -> repo.save(create.apply(id, value)));
     log.debug("Delta written: {}", delta);
     applicationEventPublisher.publishEvent(toDto.apply(delta, interval));

src/main/java/de/ph87/data/series/data/delta/meter/Meter.java

@@ -0,0 +1,49 @@
+package de.ph87.data.series.data.delta.meter;
+
+import de.ph87.data.series.Series;
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.Version;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.NonNull;
+import lombok.ToString;
+
+import java.time.ZonedDateTime;
+
+@Entity
+@Getter
+@ToString
+@NoArgsConstructor
+public class Meter {
+
+  @Id
+  @GeneratedValue(strategy = GenerationType.IDENTITY)
+  private long id;
+
+  @Version
+  private long version;
+
+  @NonNull
+  @ManyToOne(optional = false)
+  private Series series;
+
+  @NonNull
+  @Column(nullable = false)
+  private String number;
+
+  @NonNull
+  @Column(nullable = false)
+  private ZonedDateTime first;
+
+  public Meter(@NonNull final Series series, @NonNull final String number, @NonNull final ZonedDateTime date) {
+    this.series = series;
+    this.number = number;
+    this.first = date;
+  }
+
+}

src/main/java/de/ph87/data/series/data/delta/meter/MeterDto.java

@@ -0,0 +1,30 @@
+package de.ph87.data.series.data.delta.meter;
+
+import de.ph87.data.series.SeriesDto;
+import lombok.Data;
+import lombok.NonNull;
+
+import java.time.ZonedDateTime;
+
+@Data
+public class MeterDto {
+
+  private final long id;
+
+  @NonNull
+  public final SeriesDto series;
+
+  @NonNull
+  public final String number;
+
+  @NonNull
+  public final ZonedDateTime first;
+
+  public MeterDto(@NonNull final Meter meter) {
+    this.id = meter.getId();
+    this.series = new SeriesDto(meter.getSeries(), false);
+    this.number = meter.getNumber();
+    this.first = meter.getFirst();
+  }
+
+}

src/main/java/de/ph87/data/series/data/delta/meter/MeterRepository.java

@@ -0,0 +1,14 @@
+package de.ph87.data.series.data.delta.meter;
+
+import de.ph87.data.series.Series;
+import lombok.NonNull;
+import org.springframework.data.repository.ListCrudRepository;
+
+import java.util.Optional;
+
+public interface MeterRepository extends ListCrudRepository<Meter, Long> {
+
+  @NonNull
+  Optional<Meter> findFirstBySeriesOrderByFirstDesc(@NonNull Series series);
+
+}

src/main/java/de/ph87/data/series/data/delta/meter/MeterService.java

@@ -0,0 +1,28 @@
+package de.ph87.data.series.data.delta.meter;
+
+import de.ph87.data.series.Series;
+import lombok.NonNull;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.time.ZonedDateTime;
+
+@Slf4j
+@Service
+@RequiredArgsConstructor
+public class MeterService {
+
+  private final MeterRepository meterRepository;
+
+  @NonNull
+  @Transactional
+  public Meter getLastValidBySeriesAndNumberOrCreate(@NonNull final Series series, @NonNull final String number, @NonNull final ZonedDateTime date) {
+    return meterRepository
+      .findFirstBySeriesOrderByFirstDesc(series)
+      .filter(meter -> meter.getNumber().equals(number))
+      .orElseGet(() -> meterRepository.save(new Meter(series, number, date)));
+  }
+
+}

src/main/java/de/ph87/data/topic/Topic.java

@@ -72,6 +72,16 @@ public class Topic extends AbstractEntityLog {
   @Column(nullable = false)
   private String timestampQuery = "";
 
+  @Setter
+  @NonNull
+  @Column(nullable = false)
+  private String meterNumberQuery = "";
+
+  @Setter
+  @NonNull
+  @Column(nullable = false)
+  private String meterNumberLast = "";
+
   @NonNull
   @ToString.Exclude
   @ElementCollection(fetch = FetchType.EAGER)

src/main/java/de/ph87/data/topic/TopicDto.java

@@ -36,6 +36,12 @@ public class TopicDto implements IWebsocketMessage {
   @Nullable
   public final ZonedDateTime timestampLast;
 
+  @NonNull
+  public final String meterNumberQuery;
+
+  @Nullable
+  public final String meterNumberLast;
+
   @NonNull
   public final List<TopicQueryDto> queries;
 
@@ -55,6 +61,8 @@ public class TopicDto implements IWebsocketMessage {
     this.timestampType = topic.getTimestampType();
     this.timestampQuery = topic.getTimestampQuery();
     this.timestampLast = topic.getTimestampLast();
+    this.meterNumberQuery = topic.getMeterNumberQuery();
+    this.meterNumberLast = topic.getMeterNumberLast();
     this.queries = topic.getQueries().stream().map(TopicQueryDto::new).toList();
     this.error = topic.getError();
     this.payload = topic.getPayload();

src/main/java/de/ph87/data/topic/TopicReceiver.java

@@ -103,6 +103,12 @@ public class TopicReceiver {
           return;
         }
       }
+      if (series.getType() == SeriesType.DELTA) {
+        if (topic.getMeterNumberQuery().isEmpty()) {
+          log.debug("TopicQuery meterNumberQuery not set: topic={}", topic);
+          return;
+        }
+      }
 
       final Object valueRaw = json.read(query.getValueQuery());
       queryValue(valueRaw).ifPresentOrElse(
@@ -110,14 +116,17 @@ public class TopicReceiver {
           final double value = query.getFunction().apply(v) * query.getFactor();
           series.update(date, value);
           applicationEventPublisher.publishEvent(new SeriesDto(series, false));
-
           switch (series.getType()) {
             case BOOL -> {
-              final ZonedDateTime begin = "timestamp".equals(query.getBeginQuery()) ? date : queryTimestamp(json, query.getBeginQuery(), topic.getTimestampType());
+              final ZonedDateTime begin = queryTimestamp(json, query.getBeginQuery(), topic.getTimestampType());
-              final boolean terminated = !"true".equals(query.getTerminatedQuery()) && json.read(query.getTerminatedQuery(), Boolean.class);
+              final boolean terminated = queryBoolean(json, query.getTerminatedQuery());
               boolService.write(series, begin, date, value > 0, terminated);
             }
-            case DELTA -> deltaService.write(series, date, value);
+            case DELTA -> {
+              final String meterNumber = queryMeterNumber(topic, json);
+              topic.setMeterNumberLast(meterNumber);
+              deltaService.write(series, meterNumber, date, value);
+            }
             case VARYING -> varyingService.write(series, date, value);
           }
         },
@@ -128,6 +137,24 @@ public class TopicReceiver {
     }
   }
 
+  @NonNull
+  private static String queryMeterNumber(@NonNull final Topic topic, @NonNull final DocumentContext json) {
+    if (topic.getMeterNumberQuery().startsWith("\"") && topic.getMeterNumberQuery().endsWith("\"")) {
+      return topic.getMeterNumberQuery().substring(1, topic.getMeterNumberQuery().length() - 1);
+    }
+    return json.read(topic.getMeterNumberQuery(), String.class);
+  }
+
+  private static boolean queryBoolean(@NonNull final DocumentContext json, @NonNull final String terminatedQuery) {
+    if ("true".equals(terminatedQuery)) {
+      return true;
+    }
+    if ("false".equals(terminatedQuery)) {
+      return false;
+    }
+    return json.read(terminatedQuery, Boolean.class);
+  }
+
   private static Optional<Double> queryValue(final Object valueRaw) {
     if (valueRaw instanceof final Double n) {
       return Optional.of(n);
@@ -148,7 +175,7 @@ public class TopicReceiver {
 
   @NonNull
   private static ZonedDateTime queryTimestamp(@NonNull final DocumentContext json, @NonNull final String query, @NonNull final TimestampType type) {
-    if ("now".equals(query)) {
+    if ("now".equals(query) || "timestamp".equals(query)) {
       return ZonedDateTime.now();
     }
     return switch (type) {