ANSWER 4: An index can be partitioned and spread several tablespace. Each partition in the index corresponds to a segment and cannot span multiple tablespace. The primary use of a partitioned index is to minimize contention by spreading index I/O. Use of this type of segment requires the partitioning option within the database enterprise edition. ANSWER 5:
An undo segment is used by a transaction that is making changes to a database. Before changing the data or index blocks, the old value is stored in the undo segment. This allows a user to undo changes made. ANSWER 6: When user executes command such as CREATE INDEX, SELECT DISTINCT, and SELECT GROUP BY, the database server will tries to perform sorts in memory. When a sort needs more space than the space available in memory, intermediate result are written to the disk. Temporary segments are used to store these intermediate results. ANSWER 7: A column in a table may be made up of a user-defined table as in the case of items within as a segment. The inner table, which as a separate segment. ANSWER 8: A bootstrap segment, also known as a cache segment. Is created by sql.bsq script when a database is created.
This segment helps to initialize the data dictionary cache when the database is opened by an instance. The bootstrap segment cannot be queried or update. Does not require any maintenance by the database administrator.
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