Structuring data from DB

Question

Hello fellow developers,

I have a query that brings geographical areas that are contained in larger units of area; these larger units are received via params (id) and may be one or more, without limitation.

PS. Before the geographical calculations I look for the polygons that represent these units (by the id received)

Important to say that for each received unit a filter is generated using sequelize.Where and sequelize.fn which is then injected into the query:

TIME OF FILTER CREATION:

if (query.length > 1) { 
    polygons.map(p => intersectionUnitsFilter.push(this.intersectsUnits(p.coordinates, p.type)));

FUNCTION THAT EFFECTIVELY CREATES THE FILTER (Intersectunits):

intersectsUnits(encoded: string, type: string) { // mudar esse encoded
    const coords: any = encoded
    
    let wkt = wktParser.convert({
      type: type,
      coordinates: coords,
    });
    
    const polygon = Sequelize.fn('ST_GeomFromText', wkt, 4326);
    const intersects = Sequelize.fn('ST_Intersects', Sequelize.fn('ST_SetSRID', Sequelize.col('polygon'), 4326), polygon);
    const intersectionFilter = Sequelize.where(intersects, true); // maybe i can add some code here to change the query and add some column

    return intersectionFilter;
  }

Just to contextualize all this, this is the moment of the final query => The code that inserts the filter generated from units is injected into the Filters variable that is used within the final query:

filters = { 
            ...filters,
            [Op.and]: {
              [Op.or]: {
                ...intersectionUnitsFilter
              }
            }
          }
        }
        
      }

      if (subfilters.length) {
        filters = {
          ...filters,
          [Op.or]: subfilters
        }
      }

      const limit = params.limit ? params.limit : 1000;
      let areas = await Area.findAll({
        where: filters,
        include: relationships,
        offset: params.page ? params.page * limit : 0, 
        limit: limit
      });

      return areas;
    
     

THE PROBLEM:

If I get more than 1 unit, all the filtered areas come mixed together, there is no distinction about the filter that was applied in a specific area, that is, I wouldn’t know which unit belongs to a certain area, I can only say that all the results are contained in one area or another and this makes some conditions difficult there at the frontend.

ATTEMPTS TO RESOLVE:

1 - First I tried to iterate through the filters and for each filter set a filter variable and inject in the query. In this way I would make queries separately, receiving for each iteration an array with areas belonging to ONE unit only. I could for example apply a Object.assign and build objects identifying which unit that array belongs to. I had difficulties because the await does not work inside callbacks and I was confused to make a Promise that was a wrapper for the whole query.

2 - I searched insistently for sequelize commands and types of queries that could do this work directly in the database, without success.

There is an easy and quick solution to the problem?