Re: [FLIGHT] Sending multiple record batches with different schemas

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------------------ Original ------------------
From:                                                                           
                                             "user"                             
                                                       <lidav...@apache.org&gt;;
Date:&nbsp;Thu, Sep 8, 2022 05:12 AM
To:&nbsp;"dl"<user@arrow.apache.org&gt;;

Subject:&nbsp;Re: [FLIGHT] Sending multiple record batches with different 
schemas



 You can combine multiple schemas into a single schema as a union of struct 
types (since a struct is effectively the same as a batch), that is the closest 
thing you can get to having two separate schemas within one IPC stream right 
now. There was some discussion of various ways to relax this before [1] but the 
discussion died, I think because there were several distinct concepts being 
tied up into "schema evolution".



[1]: https://lists.apache.org/thread/zs31trnyhbofhvndtdrrvkvm82p8pscq



-David



On Wed, Sep 7, 2022, at 16:59, Olo Sawyerr wrote:

Hi,



Hope you're well.



I'm using arrow flight JAVA client -&gt; GO Server. I'm trying to return 2 
RecordBatches from the server to the client using a single ticket in a DoGet. 
Both RecordBatches have different schemas (length an width) but they are a 
"Pair" of results and belong / are  generated together. What's the cleanest way 
to achieve this using the DoGet?



I initially thought of sending one RecordBatch as metadata and the other as the 
Record payload. But this didn't feel natural. 



Any ideas?



Regards,



Olo