You are viewing a plain text version of this content. The canonical link for it is here.
Posted to github@arrow.apache.org by GitBox <gi...@apache.org> on 2020/11/16 19:20:15 UTC

[GitHub] [arrow] olgacarpenter opened a new issue #8684: Adding nullable columns to RecordBatch

olgacarpenter opened a new issue #8684:
URL: https://github.com/apache/arrow/issues/8684


   Hello, 
   I am very new to this library in C#, so forgive my ignorance.
   
   I am trying to create an arrow file from database rows.  If I didn't have nullable properties in my model, I can accomplish this easily by following the [example](https://github.com/apache/arrow/blob/master/csharp/examples/FluentBuilderExample/Program.cs) on this repo.  However, I do have nullable columns and I've been struggling trying to make it work.
   
   After digging a little more, i modified my code to be:
   `var memoryAllocator = new NativeMemoryAllocator(alignment: 64);
               IEnumerable<Visit> visits = _context.Visit.Take(10).AsEnumerable<Visit>();
   var recordBatch = new RecordBatch.Builder(memoryAllocator)
                   .Append("TotalCharges", true, col => col.Float(array => visits.Select(x => x.TotalCharges != null ? array.Append((float)x.TotalCharges) : array.AppendNull())))
                   .Build();`
   
   I don't get any errors from this but the file seems to be in invalid format.  It doesn't open.
   Any ideas on what i'm doing wrong and how to fix it?  
   
   Help is appreciated!


----------------------------------------------------------------
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.

For queries about this service, please contact Infrastructure at:
users@infra.apache.org

[GitHub] [arrow] jorgecarleitao commented on issue #8684: Adding nullable columns to RecordBatch

Posted by GitBox <gi...@apache.org>.
jorgecarleitao commented on issue #8684:
URL: https://github.com/apache/arrow/issues/8684#issuecomment-729037778


   Hey @olgacarpenter we generally do not use the github issues and instead rely on mailing lists, e.g. user@arrow.apache.org. Could you post this question over there?


----------------------------------------------------------------
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.

For queries about this service, please contact Infrastructure at:
users@infra.apache.org

[GitHub] [arrow] wesm closed issue #8684: Adding nullable columns to RecordBatch

Posted by GitBox <gi...@apache.org>.
wesm closed issue #8684:
URL: https://github.com/apache/arrow/issues/8684


   


----------------------------------------------------------------
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.

For queries about this service, please contact Infrastructure at:
users@infra.apache.org