Add SQL query for flexbox and grid adoption analysis

Author: aarontgrogg

sql/2025/css/flexbox_grid.sql

@@ -0,0 +1,40 @@
+#standardSQL
+# flexbox and grid adoption
+WITH totals AS (
+  SELECT
+    date,
+    client,
+    COUNT(DISTINCT root_page) AS total
+  FROM
+    `httparchive.crawl.pages`
+  WHERE
+    date IN ('2025-07-01', '2024-06-01', '2023-07-01', '2022-06-01', '2021-07-01', '2020-08-01', '2019-07-01')
+  GROUP BY
+    date,
+    client
+)
+
+SELECT
+  SUBSTR(CAST(date AS STRING), 0, 4) AS year,
+  client,
+  IF(feat.feature = 'CSSFlexibleBox', 'flexbox', 'grid') AS layout,
+  COUNT(DISTINCT root_page) AS freq,
+  total,
+  COUNT(DISTINCT root_page) / total AS pct
+FROM
+  `httparchive.crawl.pages`,
+  UNNEST (features) AS feat
+JOIN
+  totals
+USING (date, client)
+WHERE
+  date IN ('2025-07-01', '2024-06-01', '2023-07-01', '2022-06-01', '2021-07-01', '2020-08-01', '2019-07-01') AND
+  feature IN ('CSSFlexibleBox', 'CSSGridLayout')
+GROUP BY
+  year,
+  client,
+  layout,
+  total
+ORDER BY
+  year DESC,
+  pct DESC