AWS Athena V2/PrestoDB：在右侧子查询中引用左侧行

Question

I have a usecase where I need to support recursive relationship fetching, with a possible LIMIT clause on each depth of relationship.

Something like:

SELECT ... FROM artists LIMIT 5
for artist in artists:

    SELECT ... FROM albums WHERE artist_id = artist.id LIMIT 3
    for album in albums:

        SELECT ... FROM tracks WHERE album_id = albums.id LIMIT 2

In Postgres/MySQL etc, you can do this with LATERAL / CROSS APPLY .

select *
from
  lateral (
    select ...
    from `Artist`
    limit 5
  ) as `Artist`,

  lateral (
    select ...
    from `Album`
    where `Artist`.`ArtistId` = `Album`.`ArtistId`
    limit 3
  ) as `Album`

Athena says that it supports CROSS JOIN LATERAL :

• https://docs.aws.amazon.com/athena/latest/ug/engine-versions-reference.html

However if you try to use this with a correlated subquery, it wigs out

Is there any way to emulate the behavior of LATERAL / CROSS APPLY with the variant of SQL that Athena V2 supports?

• 

EDIT: Here is some sample data and expected output

{"ArtistId":"1","Name":"AC/DC"}
{"ArtistId":"2","Name":"Accept"}

{"AlbumId":"1","Title":"For Those About To Rock We Salute You","ArtistId":"1"}
{"AlbumId":"2","Title":"Balls to the Wall","ArtistId":"2"}
{"AlbumId":"3","Title":"Restless and Wild","ArtistId":"2"}
{"AlbumId":"4","Title":"Let There Be Rock","ArtistId":"1"}
{"AlbumId":"5","Title":"Third Thing","ArtistId":"2"}

SELECT *
FROM LATERAL (SELECT * FROM Artist LIMIT 2) AS artist,
     LATERAL (SELECT * FROM Album WHERE artist.ArtistId = Album.ArtistId LIMIT 2) AS album

ArtistId	Name	AlbumId	Title
1	AC/DC	1	For Those About To Rock We Salute You
1	AC/DC	4	Let There Be Rock
2	Accept	2	Balls to the Wall
2	Accept	3	Restless and Wild

Answer 1

You can simulate this behaviour using row_number window function:

-- sample data
WITH artists(ArtistId,Name) AS (
    VALUES (1,'AC/DC'),
        (2,'Accept'),
        (3,'Behemoth')
),
albums(AlbumId,Title,ArtistId) as (
    VALUES (1,'For Those About To Rock We Salute You',1),
        (2,'Balls to the Wall',2),
        (3,'Restless and Wild',2),
        (4,'Let There Be Rock',1),
        (5,'Third Thing',2)
)

-- query
select a.ArtistId, Name, AlbumId, Title
from (select * from artists limit 2) a
join (
    select *, row_number() over (partition by ArtistId order by AlbumId) rn
    from albums
) al on a.ArtistId = al.ArtistId and al.rn <=2

Output:

ArtistId	Name	AlbumId	Title
1	AC/DC	1	For Those About To Rock We Salute You
1	AC/DC	4	Let There Be Rock
2	Accept	2	Balls to the Wall
2	Accept	3	Restless and Wild