Multi-Category/Tag Filters

Sometimes you may want to filter documents in Chroma based on multiple categories or tags e.g. games and movies. Unfortunately, Chroma does not yet support complex data-types like lists or sets so that one can use a single metadata field to store and filter by. It is also not possible to use fuzzy search LIKE queries on metadata fields.

To solve this problem without introducing a complex logic on the client side, we suggest the following approach.

When adding document to a collection add each category it belongs to as a boolean metadata field:

No Empty Categories/Tags

Only add categories an item belongs to with flags set to True. Do not add categories an item does not belong to and set the flag to False.

collection.add(
    ids=[f"{uuid.uuid4()}"],
    documents=["This is a document"],
    metadatas=[{"games": True, "movies": True}],
)

When querying documents, you can filter by multiple categories by using the where parameter:

results = collection.query(
    query_texts=["This is a query document"],
    where={"games": True},
)
# or a more complex query
results = collection.query(
    query_texts=["This is a query document"],
    where={"$or": [{"games": True}, {"movies": True}]},
)