Veritas Storage Foundation 5.1 SP1: Storage and Availability Management for Oracle (5900-1504, April 2011)

How SmartTier for Oracle works
In an Oracle database environment, the access age rule can be applied to archivelog
files and Flashback files. Oracle updates the header of each datafile at every
database checkpoint and hence access age rules cannot be used for datafiles. For
a partitioned table, we can use the name base rule to relocate files belonging to a
given partition, for instance last year, to the secondary storage tier. However if
a database does not have partitioned tables, current methods for relocation do
not fit to the Oracle database environment. To understand how to optimize file
relocation for Oracle databases, we need to study how Oracle stores objects in the
database.
How partitions change the way Oracle stores database objects
Oracle Database stores data logically in tablespaces and physically in datafiles
associated with the corresponding tablespace. A database is divided into one or
more logical storage units called tablespaces. A tablespace in an Oracle database
consists of one or more physical datafiles. A datafile can be associated with only
one tablespace and only one database. Tablespaces are divided into logical units
of storage called segments, which are further divided into extents. Extents are a
collection of contiguous blocks in a datafile. Tables are the basic unit of data
storage in an Oracle database. Data is stored in rows and columns. Tables are
defined with a table name (such as employees) and set of columns. Usually a table
resides within a single tablespace except for partitioned tables. A partitioned table
is a table which has one or more partitions, and each partition may reside on a
different tablespace.
Understanding storage tiering with SmartTier
How SmartTier for Oracle works
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