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mvn -Pgenerate -Ddatabase=${database} -DreleaseVersion=${releaseVersion} clean package
releaseVersion should be set to the version without the -SNAPSHOT. E.g. 5.12
That command produces the datafiles in activiti-upgrade/src/test/resources/org/activiti/db/${newVersion}/data. If you do this before you branched the code, bear in mind that the directory name might contains the -SNAPSHOT. Then you can just manually change the directory name of the version.
Run that generate profile for every database.
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