aggregate framework returned empty array

Amaraa_G · 2024-09-02T09:23:24.557Z

Hi all?
I need test my database. When I execute below aggregate query, returns empty array. In that case main collection has data and other collections are empty.

[
        {
          $lookup: {
            from: 'MM_AdministrationCode',
            localField: '_id',
            foreignField: '_id',
            as: 'administrationCode'
          }
        },
        {
          $lookup: {
            from: 'MM_Manpower',
            localField: '_id',
            foreignField: '_id',
            as: 'manpower'
          }
        },
        {
          $lookup: {
            from: 'MM_Arena',
            localField: '_id',
            foreignField: 'complexId',
            as: 'arenas'
          }
        },
        {
          $lookup: {
            from: 'MM_FileMulti',
            localField: '_id',
            foreignField: '_id',
            as: 'photos'
          }
        },
        {
          $lookup: {
            from: 'MM_Ownership',
            localField: '_id',
            foreignField: '_id',
            as: 'ownership'
          }
        },
        { $unwind: { path: '$administrationCode' } },
        { $unwind: { path: '$manpower' } },
        { $unwind: { path: '$photos' } },
        { $unwind: { path: '$ownership' } },
        { $unwind: { path: '$ownership.owners' } },
        {
          $lookup: {
            from: 'MM_Organisation',
            localField: 'ownership.owners.ownerId',
            foreignField: '_id',
            as: 'ownership.owners.ownerInfo'
          }
        },
        { $unwind: { path: '$ownership.owners.ownerInfo' } },
        {
          $group: {
            _id: '$_id',
            owners: { $push: '$ownership.owners' },
            complexName: { $first: '$complexName' },
            introduction: { $first: '$introduction' },
            photos: { $first: '$photos' },
            administrationCode: { $first: '$administrationCode' },
            manpower: { $first: '$manpower' },
            arenas: { $first: '$arenas' }
          }
        },
        {
          $project: {
            _id: 1,
            complexName: 1,
            introduction: 1,
            photos: 1,
            administrationCode: 1,
            owners: 1,
            arenas: 1,
            arenaCount: {
              $size: '$arenas'
            },
            manpower: 1,
            workerCount: {
              $add: [
                '$manpower.cheifNumber',
                '$manpower.trainerFemaleNumber',
                '$manpower.trainerMaleNumber',
                '$manpower.servantFemaleNumber',
                '$manpower.servantMaleNumber'
              ]
            }
          }
        }
      ]

Where is problem? I hope some one fix help me. Thank you.

John_Sewell · 2024-09-02T09:53:06.225Z

It would make life easier to help look at your issues if you provided example data, preferably in a mongo playground environment with data setup.

mongoplayground.net

Mongo playground

Mongo playground: a simple sandbox to test and share MongoDB queries online

John_Sewell · 2024-09-02T10:04:59.862Z

Scanning the lookups are all the _ids the same in all collections for matching data? Is the PK the same in all collections?