<loadData> and database-independent way of using next sequence number?

Hi,

Using Liquibase 3.3.2. I'm trying to write a db-independent way of specifying that the PK's for my data are to be the next value from a given sequence. I've read and see how to make it specific to a given DB type, but I'd like to be able to write my changeSet to be more database independent. I know I could write multiple changeSets, one for each DB type I need to support - but that's getting unwieldy. Looking at the dbchangelog-3.3.xsd, the "column" attribute group has some promising elements such as 'valueSequenceNext', or 'defaultValueSequenceNext'. However, those elements aren't enabled in the "column" element defined inside the loadData, so are unavailable.

Anyone able to help out here?

Thanks!

Bob.