alamb commented on PR #2177:
URL: 
https://github.com/apache/arrow-datafusion/pull/2177#issuecomment-1169115997

   > @alamb Hello! Have you had already time to check the PR?
   
   Hi @gandronchik  sadly I have not had a chance. I apologize for my lack of 
bandwidth but it is hard to find sufficient contiguous time to review such 
large PRs when I don't have the background context.
   
   My core problem is that I don't understand (despite your admirable attempts 
to clarify) what this PR is trying to implement, so it is very hard to evaluate 
the code to see if it is implementing what is desired (because I don't 
understand what is desired).
   
   For example, all the examples of "set returning functions" in the links you 
shared in postgres appear to use those functions as elements in the `FROM` 
clause. For example, 
   
   ```sql
   select * from unnest(ARRAY[1,2], ARRAY['foo','bar','baz']) as x(a,b) →
   ```
   
   So I am struggling to understand examples you share in the PR's description 
that show using these functions in combination with a column 🤔 
   
   ```sql
   select table_fun(1, col) from (select 2 col union all select 3 col) t;
   ```
   
   So what would you think about implementing more general user defined table 
functions (that can return RecordBatches / streams as we have discussed above)? 
I think others would also likely use such functionality and it seems like it 
would satisfy  the usecases from cube.js (?)
   
   
   
   


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: [email protected]

For queries about this service, please contact Infrastructure at:
[email protected]

Reply via email to