Generate Series Alternative for Snowflake 有效但生成的列表不完整

Question

我正在考虑创建一个列表，我可以在其中查看在给定时间内生成了多少个 ID。因为我想独立于日期的小时提前显示从 8 到 21 的小时数，所以我使用了生成系列，现在需要找到 Snowfake 的等价物。这是我的查询：

series as  (
    SELECT seq4() as Hour 
    FROM TABLE(GENERATOR(rowcount => 21)) 
    where Hour between 7 and 20 
    ORDER BY Hour), 
ID_table as (
    select extract(hour from date) as "Hour", 
    count(ID) as "Count" 
    from ID_table 
    group by 1) 
 select (Hour.Hour) + 1 AS "Hour",
 id."Count", 
 from series as Hour
 left join ID_table as id on id."Hour" = Hour.Hour 
 order by Hour.Hour;

出于某种原因，我只能看到 8 到 16 点，但是，我希望它显示 8-21 点，可能是什么问题？

Answer 1

您应该始终考虑到 SEQ() 函数不能保证间隙，因此为了生成范围，我建议您使用 ROW_NUMBER() 函数：

https://community.snowflake.com/s/article/Generate-gap-free-sequences-of-numbers-and-dates

无论如何，当我测试它时，我看到它 returns 预期数字：

SELECT seq4() as Hour FROM TABLE(GENERATOR(rowcount => 21));
-- returnns numbers from 0 to 20

SELECT seq4() as Hour FROM TABLE(GENERATOR(rowcount => 21)) where Hour between 7 and 20 order by hour;
-- returnns numbers from 7 to 20

with series as (SELECT seq4() as Hour FROM TABLE(GENERATOR(rowcount => 21)) where Hour between 7 and 20 ORDER BY Hour)
select (Hour.Hour) + 1 AS "Hour"
from series as Hour;
-- returnns numbers from 8 to 21

会不会是browser/UI的东西？

Generate Series Alternative for Snowflake 有效但生成的列表不完整

Generate Series Alternative for Snowflake works but generates an incomplete list

list

time

schema

snowflake-cloud-data-platform

generate