Ok, I see, you are working on a model. In this case you need indeed to propagate your changes to your server. The actual approach depends on what you want to achive. You can either forward engineer your entire model, which will recreate all objects or you synchronize model and server, which is a two-way merge (changes from the model are applied to db objects and vice versa). The first option obviously destroys data (if there's any) while the second does not.
I have however a problem to understand your sentence "Then I created a new connection with the model". Can you describe in detail what you did? As it stands it doesn't make much sense, as there are no connections associated with a model. Connections in the context of WB are setups to MySQL servers (and other servers in case of migration). They are entities on their own and do not depend on anything else in WB. The forward and the sync processes can make use of such connections to have a server to work with. The very same connection(s) can also be used to do admin or SQL work in other sections of WB (not in modeling, though).
Once you applied your changes you should see also the changed table columns.
Mike
Mike Lischke, MySQL Developer Tools
Oracle Corporation
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