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Go Back  dBforums > Database Server Software > Oracle > Determining reusable blocks per table

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Old 02-07-12, 16:24
theowne theowne is offline
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Determining reusable blocks per table

Hi all, a question.

dba_segments and dba_free_space provides a convenient way to look at space that is owned by a table or object compared to the size of datafile.

However, I know that when a table deletes many rows, there is free space left within it. This space can be reused by the table itself. But to an outsider, it appears to take up the same amount of space in dba_segments, and dba_free_space. So a table may appear to be at 20mb size, but have a lot of reusable space within it, meaning it won't grow for a long time.

Is there a way for me to query how much reusable space a table has? I think these are called freelists.
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Old 02-07-12, 16:31
anacedent anacedent is offline
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>Is there a way for me to query how much reusable space a table has?
Yes, but nontrivial to do.
Besides what can & do you plan on doing with any such answer;
since you have *NO* control over where Oracle actually places data upon INSERT?
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