Oracle: Unterschied zwischen DROP und UNUSE

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Quelle: https://asktom.oracle.com/pls/apex/f?p=100:11:0::::P11_QUESTION_ID:1381803609490

alter table T drop column....
alter table T set unused.....


what different between those two alter command will impact rbs and redo?







Followup   April 4, 2002 - 7pm UTC:




alter set unused -- thats a flag delete.  no effect on undo/redo really.

alter drop -- thats a rewrite, potentially big effect on undo/redo.












































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