How to get the length of a repeated nested field in bigquery

Question

I have a table in bigquery where I have a repeated nested field called author_names.

How can I get the length of the repeated nested field author_names? e.g. for article_id = 2049807276, the length of the author names would be 2.

I prefer the standard-sql syntax in bigquery.

Answer 1

You should use ARRAY_LENGTH() function

as in

#standard SQL
SELECT article_id, ARRAY_LENGTH(author_names) len
FROM `table`