[jira] [Commented] (ARROW-4975) [C++] Support concatenation of UnionArrays
[ https://issues.apache.org/jira/browse/ARROW-4975?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17661997#comment-17661997 ] Rok Mihevc commented on ARROW-4975: --- This issue has been migrated to [issue
[jira] [Commented] (ARROW-4975) [C++] Support concatenation of UnionArrays
[ https://issues.apache.org/jira/browse/ARROW-4975?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=17448225#comment-17448225 ] Antoine Pitrou commented on ARROW-4975: --- This should be almost trivial for sparse unions and would