Hi Ashish,

Bigquery supports AVRO extract so you can use either Composer or self-hosted Airflow with BigQuery Operator (This will give you the option of extracted file format where you can choose AVRO). Dataflow might not be needed unless and until you want some transformation of data before writing it to GCS.

Check this “bigquery_to_gcs operator”: https://airflow.apache.org/_api/airflow/contrib/operators/bigquery_to_gcs/index.html#airflow.contrib.operators.bigquery_to_gcs.BigQueryToCloudStorageOperator