BigQuery: flatten two repeated columns

Question

I am currently working with a very simple table on BigQuery and each row has two repeated columns class_numbers [REPEATED INTEGER] and class_

Answer 1

Using standard SQL, you can use UNNEST(...) WITH OFFSET. For example,

SELECT
  class_number,
  class_descriptions[OFFSET(off)] AS class_description
FROM MyTable,
  UNNEST(class_numbers) AS class_number WITH OFFSET off;