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

[nandagopal]

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

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.

How do you switch from an init.ora file to a spfile?

Issue the create spfile from pfile command.


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

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.