infrastructure-qdrant-collection-de-qdrantvectorstore-can-unintentionally-delete-an-ex-3b9115f6

THEN Replace the cached boolean flag with a runtime collection existence check before adding vectors. Use `create_collection` instead of `recreate_collection` to avoid accidental deletion. Ensure the existence check only returns False on definitive non-existence (e.g., 404) and raises on other errors to prevent silent data loss.

def _collection_exists(self, collection_name: str) -> bool:
    try:
        self._client.get_collection(collection_name)
        return True
    except (UnexpectedResponse, RpcError, ValueError) as e:
        if hasattr(e, 'status_code') and e.status_code == 404:
            return False
        raise  # propagate other errors

def add(self, nodes, **kwargs):
    if len(nodes) > 0:
        if not self._collection_exists(self.collection_name):
            self._client.create_collection(
                collection_name=self.collection_name,
                vectors_config=rest.VectorParams(...)
            )