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Index fragmentation

What about ALTER INDEX … SHRINK SPACE ?

By Franck Pachot . I have recently published a script to check index fragmentation. But then, do you COALESCE or REBUILD? Well, there also is another option: ALTER INDEX SHRINK SPACE. Let’s compare all those index defragmentation operations. Fragmented index I have an index created when the table had 1 million rows. Then, I deleted 90% of the rows. Here… 

How to measure Oracle index fragmentation

By Franck Pachot . At Oracle Open World 2014, or rather the Oaktable World, Chris Antognini has presented ‘Indexes: Structure, Splits and Free Space Management Internals’. It’s not something new, but it’s still something that is not always well understood: how index space is managed, block splits, fragmentation, coalesce and rebuilds. Kyle Hailey has made a video of it available…