Explain the difference between a data block, an extent and a segment.

Explain the difference between a data block, an extent
and a segment.
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1 Answer

Answer :

A data block is the smallest unit of logical storage for a database
object. As objects grow they take chunks of additional storage that are
composed of contiguous data blocks. These groupings of contiguous
data blocks are called extents. All the extents that an object takes
when grouped together are considered the segment of the database
object.
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