Daniel Nugent created ARROW-6625: ------------------------------------ Summary: 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
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)