使用 pymongo 将 json 文档的所有值更新为默认值

Question

I have a JSON document in the following format,

{
    "_id": ObjectId("54a2462820fb5b6068b45b05"),
    "Ref": 1,
    "a": {
        "b": "value1",
        "c": "value2",
        "d": {
            "e": "value3"
        }
    }
}

I need to update values of all the keys even nested (Ref,b,c,e) except _id to some default value say 'na' at once. I think it is not possible using mongo Query.

Any way to do this in pymongo programmatically? Thanks in advance !!!

Answer 1

Use a recursive function to Update values of all keys except _id to default value. Then use save() to update your documents.

def recurse_keys(document):
    for key in document.keys():
        if isinstance(document[key], dict):
            recurse_keys(document[key])
        else:
            if key != '_id':
                document[key]='NA'


//update your document, save behaves as upsert with '_id' supplied.
db.collection.save(document)