If your DB is applied with patch#8198906, then beware that you may run into corruption when extending the table manually.
This patch is obselete now. You have to uninstall and install 9711859.
If your shop is managing 1000s of DBs then how to find out on which installation this patch is applied.
If these DBs are managed in OEM, then you can use below query
select * from mgmt_inv_patch_fixed_bug where bug_number=8198906;
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