我有多个列表,我想使用SQL构造这些列表的笛卡尔联接。我想知道您是否比下面的方法更干净。谢谢
with letters_table AS (Select letters from UNNEST(['A','B','C']) letters)
,numbers_table AS (Select numbers from UNNEST([1,2,3]) numbers)
select letters,numbers,concat(letters,'-',numbers) as concat
from letters_table
cross join
numbers_table
您的查询看起来不错,但是没有理由使用CTE:
select letter, number, concat(letter, '-', number) as concat
from unnest(['A', 'B', 'C']) letter cross join
unnest([1, 2, 3]) number