There are few global constants in OmegaWiki such as $wgDefaultClassMids, $wgIso639_3CollectionId, some access rights, etc.

Since they mostly refer to certain dynamically assigned ID values used as index values, they likely depend on the individual data sets stored in the database and need either to be switched with the data set context or be held in a data structure per data set.

Maybe the switching already occurs, but I have not seen an indication of it. Thus this report, to be on the safe side.