def delete(self, key: str, collection: str = DEFAULT_COLLECTION) -> bool:
        """
        Delete a value from the store.

        Args:
            key (str): key
            collection (str): collection name

        """
        from sqlalchemy import delete

        self._initialize()
        with self._session() as session:
            result = session.execute(
                delete(self._table_class)
                .filter_by(namespace=collection)
                .filter_by(key=key)
            )
            session.commit()
        return result.rowcount > 0

        Delete a value from the store.

        Args:
            key (str): key
            collection (str): collection name

        
llama-index-integrations/storage/kvstore/llama-index-storage-kvstore-postgres/llama_index/storage/kvstore/postgres/base.py