SELECT f.repo_name f.path, c.pkey FROM [bigquery-public-data:github_repos.files} f //Query all matches for id that fits the key parameters.// JOIN ( SELECT id, REGEXP_EXTRACT(content, r'(?:^|[^a-zA-Z0=9])(5[HJK][123456789abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ]{48,49})(?:$|[^a-zA-Z0-9])') AS pkey FROM [bigquery-public-data:github_repos.contents] WHERE REGEXP_MATCH(content, r'(?:^|[^a-zA-Z0=9])(5[HJK][123456789abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ]{48,49})(?:$|[^a-zA-Z0-9])') c ON f.id = c.id