小编Sco*_*den的帖子

我很难将这两个功能组合到一个查询中，例如：

WITH time_values AS (
    SELECT
        (end_time - start_time) * 1.0 / 3600000000 AS num_hours
    FROM table
    WHERE
        end_time >= 1493596800000000
        AND start_time < 1493683200000000
)

SELECT
    PERCENTILE_DISC(0.25) WITHIN GROUP (ORDER BY num_hours) OVER() AS p25,
    PERCENTILE_DISC(0.50) WITHIN GROUP (ORDER BY num_hours) OVER() AS p50,
    PERCENTILE_DISC(0.80) WITHIN GROUP (ORDER BY num_hours) OVER() AS p80,
    PERCENTILE_DISC(0.99) WITHIN GROUP (ORDER BY num_hours) OVER() AS p99,
    AVG(num_hours)
FROM time_values;

这返回 ERROR: column "time_values.num_hours" must appear in the GROUP BY clause or be used …

在PostgreSQL中获取日期范围显示了如何在PostgreSQL中获取日期范围。但是，Redshift不支持generate_series()：

ans=> select (generate_series('2012-06-29', '2012-07-03', '1 day'::interval))::date;
ERROR:  function generate_series("unknown", "unknown", interval) does not exist
HINT:  No function matches the given name and argument types. You may need to add explicit type casts.

有没有办法复制generate_series()Redshift中的内容？