I'm new in MongoDB.
I have two collections with names adverb and categories.
adverb fields are
{
    "advId": "myid",
    "advTitle": "myTitle",
    "advDescription": "test description",
    "fromUser": "userid",
    "subCategoryId": "catid",
    "advLabel": "1",
    "cityId": "cityid",
    "areaName": "areaName",
    "chatState": true,
    "geoPosition": {
        "latitude": 21.61980691353274,
        "longitude": 51.519725019871956
    },
    "advImages": [],
    "timeStamp": 1646670847761,
    "visibility": false
}
and categories collection with fields
{
    "catId": "catId",
    "catTitle": "catTitle",
    "catSub": [{
        "subId": "subId",
        "subTitle": "آپارتمان"
    }, {
        "subId": "subId",
        "subTitle": "ویلایی"
    }]
}
and I want to join "adverb's subCategoryId" with "subId on catSub's categories collection" that catSub is an array with object values How can I do this? tnx.
 
    