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Multi-model pattern

Documents with different schemas could be stored in a single collection and managed correctly. UnionDoc class is used for this.

It supports find and aggregate methods. For find, it will fetch all the found documents into the respective Document classes.

Documents that have union_doc in their settings can still be used in find and other queries. Queries of one such class will not see the data of others.

Example

Create documents:

from beanie import Document, UnionDoc


class Parent(UnionDoc):  # Union
    class Settings:
        name = "union_doc_collection"  # Collection name


class One(Document):
    int_field: int = 0
    shared: int = 0        

    class Settings:
        union_doc = Parent


class Two(Document):
    str_field: str = "test"
    shared: int = 0

    class Settings:
        union_doc = Parent

The schemas could be incompatible.

Insert a document

await One().insert()
await One().insert()
await One().insert()

await Two().insert()

Find all the documents of the first type:

docs = await One.all().to_list()
print(len(docs))

>> 3 # It found only documents of class One

Of the second type:

docs = await Two.all().to_list()
print(len(docs))

>> 1 # It found only documents of class One

Of both:

docs = await Parent.all().to_list()
print(len(docs))

>> 4 # instances of the both classes will be in the output here

Aggregations will work separately for these two document classes too.