text: #standardSQL
  # 17_10b: Common vary headers as seen from CDNs
  
  SELECT
    client, firstHtml, vary,
    IF(_cdn_provider != '', 'CDN', 'Origin') AS source,
    COUNT(0) AS total
  FROM
    `httparchive.almanac.requests`,
    UNNEST(split(REGEXP_REPLACE(REGEXP_REPLACE(LOWER(resp_vary), '\"', ''), '[, ]+|\\\\0', ','), ',')) AS vary
  WHERE
    date = '2019-07-01'
  GROUP BY
    client, firstHtml, vary, source
  HAVING
    vary <> '' AND vary IS NOT NULL
  ORDER BY
    client DESC,
    firstHtml DESC,
    total DESC
  