Beginning Oracle Database 11g Administration From Novice to Professional

CHAPTER 3 ORACLE ARCHITECTURE 61
database is used to collectively indicate the data
files and supporting files on the storage disks attached to the host computer. The
word instance is used to indicate the various computer processes resident in computer
memory and memory areas shared by these processes.
instances and databases is either one-to-one (one instance per database) or
many-to-one (multiple instances per database).
stored in the environment variable .
, , and .
assigned to one tablespace and shares the space with the other tables assigned to
the same tablespace. Data files can grow automatically if the database administrator
wishes. The space within data files is organized into equally sized blocks;
all data files belonging to a tablespace use the same block size. When a data table
needs more space, it grabs a contiguous range of data blocks called an extent; it is
conventional to use the same extent size for all tables in a tablespace.
memory.
micity
and durability of a transaction. Redo logs are of fixed size and are mirrored
for safety. Oracle fills the redo logs in round-robin fashion. The redo logs should
be archived when they fill up—this makes it possible to repair data files if they get
damaged.
and locations of the data files, among other things.
created when a severe error occurs.
and the log buffer. The best-known use of the shared pool is to cache query execution
plans. It is also used to store information from the data dictionary.
nated
when the user disconnects from the database. In the multithreaded server
(MTS) mode of operation, all user connections are serviced by a small number of
dispatchers and shared servers.