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Issue – The DEL tables have not been deleted after unchecking the “Keep Update Objects 4.0″ and “Keep Update Objects 4.1″ from the Config tree.

Solution -
Disable “Keep upgrade objects” configuration key after upgrade is finished and customer confirms that all data was succesully upgraded. Disabling the key results in physical removal of DEL_ tables and fields from the database (not from the AOT)

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