Filter Conditions

We have seen how to fetch data from MongoDB using find and find_one functions. But, we don’t need to fetch all the documents all the time. This is where we apply some filter conditions.

Previously we have inserted a document to the MongoDB collection with the name  field as Gyan. Let’s see how to fetch that MongoDB document using the filter condition:

table.find_one({"name":'Gyan'})

mongodb python filter

Here, we have fetched the document using the name which is a string argument. On the other hand, we have seen in the previous example that final. inserted_ids contains the Ids of the inserted documents.

If we apply the filter condition on the _id field, it will return nothing because their datatype is ObjectId. This is not the built-in datatype. We need to convert the string value to ObjectId type to apply the filter condition on _id . So first, we will define a function to convert the string value then we will fetch the MongoDB document:

from bson.objectid import ObjectId

post_id=final.inserted_ids[0]

def parser(post_id):

    document = table.find_one({'_id': ObjectId(post_id)})

    return document

parser(post_id)