Angular 9 Get variable observable from database

I am making several queries to a database (here influxdb) and mapping them to an interface. This works so far also everything. What bothers me is that I need a new function for each interface. I would like to have my code optimized so that I only need one function for each interface. Unfortunately my knowledge is not yet sufficient for this. I am looking forward to your opinions about the challenge.

import { InfluxDB } from '@influxdata/influxdb-client';
import { Observable, from } from 'rxjs';
import { map, toArray } from 'rxjs/operators';
import { url, token, org } from './env';

export class QueryService {

  static  fluxQuery1 = `from(bucket: "bucket0")
  |> range(start: xxx, stop: yyy)
  |> filter(fn: (r) => r["_measurement"] == "measure")
  |> filter(fn: (r) => r["_field"] == "value")
  |> last()`;

  static  fluxQuery2 = `from(bucket: "bucket0")
  |> range(start: zzz, stop: wwww)
  |> filter(fn: (r) => r["_measurement"] == "measure2")
  |> last()`;

  static queryApi = new InfluxDB({ url, token }).getQueryApi(org);

  constructor() {
  }

  public queryInflux1(): Observable<Inteface1[]> {
    return from(QueryService.queryApi.rows(QueryService.fluxQuery1)).pipe(
      map(({ values, tableMeta }): Inteface1 => {
        const returnvalue = tableMeta.toObject(values);
        return {
          name: returnvalue.string,
          element: returnvalue.string,
          typ: returnvalue.string
        };
      }),
      toArray() // Collect into array of rows with rxjs operator
    );
  }

    public queryInflux2(): Observable<Inteface2[]> {
    return from(QueryService.queryApi.rows(QueryService.fluxQuery2)).pipe(
      map(({ values, tableMeta }): Inteface2=> {
        const returnvalue = tableMeta.toObject(values);
        return {
          isvalid: returnvalue.boolean,
          value: returnvalue.number
        };
      }),
      toArray()
    );
  }
}

export interface Interface2{
  name: string;
  element: string;
  typ: string;
}

export interface Interface2{
  isvalid: boolean;
  value: number;
}