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Question on table fragmentation
Hi All,
Is there any way to find the follwoing two points.
1. How to know a table is how much fragmented.?
2. How to know, how much space we can claim from the table which is fragmented?
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are you using 9i or 10g above? also are you using DMTS or LMTS?
Thanks,
Vijay Tummala
Try hard to get what you like OR you will be forced to like what you get.
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It is Oracle 10g and DMTS.
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You should be using locally managed tablespaces in 10g. There is no justification whatsoever for using DMT. With LMT, fragmentation went the way of dinosaurs.
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Originally Posted by skdas
Is there any way to find the follwoing two points.
1. How to know a table is how much fragmented.?
2. How to know, how much space we can claim from the table which is fragmented?
1- Yes.
2- Provided you have up-to-date performance statistics dba_tables tells you: a) how many rows you have in your table, b) average row lenght and, c) how much overhead you have set for the table; these pieces of information allow you to tell what's your "ideal" space utilization. On the other hand dba_extents allows you to check how much space is the table actually allocating. Difference between actual nad ideal space utilization is the space you are wasting e.g. space allocated but not used to store actual data.
Pablo (Paul) Berzukov
Author of Understanding Database Administration available at amazon and other bookstores.
Disclaimer: Advice is provided to the best of my knowledge but no implicit or explicit warranties are provided. Since the advisor explicitly encourages testing any and all suggestions on a test non-production environment advisor should not held liable or responsible for any actions taken based on the given advice.
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