Compare BigQuery table schemas

compare_bq_table_schemas.py

def compare_table_schemas(client, project: str, dataset: str, 
                          table_a: str, table_b: str) -> bool:
    """Compare the schemas of two BigQuery tables. Useful for instance
    to confirm that there hasn't been a drift in the schemas for the
    production and development tables.
    
    :param client: BigQuery client object
    :param project: string - GCP project ID
    :param dataset: string - dataset name
    :param table_a:  string - table name
    :param table_b:  string - table name
    :return: bool - whether the schemas are the same
    """
    query_a = f"""
      WITH schema AS (
      SELECT * FROM {project}.{dataset}.INFORMATION_SCHEMA.COLUMNS
      WHERE table_name = f'{table_a}'
      SELECT column_name, data_type FROM schema
    """

    query_b = f"""
      WITH schema AS (
      SELECT * FROM {project}.{dataset}.INFORMATION_SCHEMA.COLUMNS
      WHERE table_name = f'{table_b}'
      SELECT column_name, data_type FROM schema
    """

    df_a = client.query(query_a).to_dataframe()
    df_b = client.query(query_b).to_dataframe()

    schema_1 = df_a.to_dict('records')
    schema_2 = df_b.to_dict('records')
    return schema_1 == schema_2