Sorry, I stand corrected !!
When I launch my Data Admin tool, I get the following message:
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Warning (Press HELP to view stack trace)
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The following databases are currently in use by running procedures:
db1,db2
Making schema changes to any of these databases at this time will cause
PROGRESS to initiate a session restart causing all unsaved work to be lost.
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OK Help
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which led me to think that online db changes are not allowed.
But in Load Data Definitions window of Data Admin tool, there is a toggle-box "Add new objects on-line". Never used this option before, so never knew what it actually did.
Cool guys... thank you !!!