Did you by any chance create multiple tables using the same name?
If so, what probably happened is that at first you created a table with a certain field was defined with type X, then you tried to create a table with the same name and an identically named field, but this time with type Y.
This would result in the error you reported, because while Tersus adds fields to the (physical) database table as they are added to the (logical) database record, it does not remove/change them from the table as they are removed/changed in the record.
To overcome this you should first review all your database record models in your application, checking that each has a unique tableName property value. If there are multiple database records with the same name, you'll need to manually change the name of one of them.
Next, assumming you are using the embedded database (hsqldb), and if there is no important data there, you can simply stop your embedded server, switch to the Navigator view (through Window -> Show View) and delete the database folder found in your project, which will be recreated (with all tables defined in the model) once you restart the server.
If there is important data you must keep, you can also edit the database file (the .script file in the database folder) using a text editor (again the server must be stopped first), but that does require indepth knowledge of hsqldb. The same is true if you've configured the project to use an alternate database.
If all this is too confusing, I reiterate the offer that you export the application and send it over, either in this thread or through the contact us page.
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