[ https://issues.apache.org/jira/browse/ARROW-6625?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16934614#comment-16934614 ]
Wes McKinney commented on ARROW-6625: ------------------------------------- Seems like a good idea. We have all the machinery available to do this in a performant way > [Python] Allow concat_tables to null or default fill missing columns > -------------------------------------------------------------------- > > Key: ARROW-6625 > URL: https://issues.apache.org/jira/browse/ARROW-6625 > Project: Apache Arrow > Issue Type: Wish > Components: Python > Reporter: Daniel Nugent > Priority: Minor > > The concat_tables function currently requires schemas to be identical across > all tables to be concat'ed together. However, tables occasionally are > conforming on type where present, but a column will be absent. > In this case, allowing for null filling (or default filling) would be ideal. > I imagine this feature would be an optional parameter on the concat_tables > function. Presumably the argument could be either a boolean in the case of > blanket null filling, or a mapping type for default filling. If a user wanted > to default fill some columns, but null fill others, they could use a None as > the value (defaultdict would make it simple to provide a blanket null fill if > only a few default value columns were desired). > If a mapping wasn't present, the function should probably raise an error. > The default behavior would be the current and thus the default value of the > parameter should be False or None. -- This message was sent by Atlassian Jira (v8.3.4#803005)