Athena/Presto 数据发现查询以推荐 JSON 模式？

Question

我有一个 Athena table (raw) 只有一列 (json)。

我有以下查询输出 json 键的频率：

SELECT key, count(*)
FROM (
  SELECT map_keys(cast(json_parse(json) AS map(varchar, json))) AS keys
  FROM raw
)
CROSS JOIN UNNEST (keys) AS t (key)
GROUP BY key

我如何扩展此查询，以便它告诉我某个特定键是否具有包含任何非数字字符的值？

[找到答案后删除失败的尝试]

Answer 1

这个有效：

SELECT k, count(*) as isPresent, sum(isNumber) as isNumber, 
          count(*)-sum(isNumber) as notIsNumber from (
               with dataset as (SELECT 
                   cast(json_parse(json) AS map(varchar, varchar)) as kv FROM raw)
               SELECT t.k, t.v, 
                      IF(TRY(cast(t.v as double)) is null, 0, 1) as isNumber 
               from dataset cross join unnest(kv) as t(k, v)
) group by k

Athena/Presto 数据发现查询以推荐 JSON 模式？

Athena/Presto data discovery query to recommend JSON schema?

amazon-athena

presto