Tuesday, June 11, 2013

Disavantages for enabling row movement on oracle tables

It will necessarily consume processing resources on your machine while running (it will 
read the table, it will delete/insert the rows at the bottom of the table to move them 
up, it will generate redo, it will generate undo).
If you had densely packed blocks with lots of "pretty much empty blocks", and the densely 
packed blocks were organized by index key value -- spraying them about the top of the table could 
hurt the clustering factor.
Do you have any application that expects rowid to be constant for a row?  If so - then it is wrong

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