 |
|
Oracle Tips by Burleson |
In this code:
DATABASE name. The name of the database,
a maximum of eight characters long.
File specifications for data files. Are of
the format: ‘filename’ SIZE integer K or M REUSE. K is for
kilobytes, M is for megabytes. REUSE specifies that if the file
already exists, reuse it. The AUTOEXTEND option is new with later
versions of Oracle7 and all of Oracle8 and is used to allow your
data files to automatically extend as needed. (Note: Be very careful
with this command, as it can use up a great deal of disk space
rather rapidly if a mistake is made during table builds or inserts.)
File specifications for log files depend on the operating system.
MAXLOGFILES, MAXDATAFILES, and MAXINSTANCES.
Set hard limits for the database; these should be set to the maximum
you ever expect.
MAXLOGMEMBERS and MAXLOGHISTORY. Hard
limits.
EXTENT MANAGEMENT. Determines whether the
extents in the SYSTEM tablespace are managed via the data dictionary
(DICTIONARY) or locally via a bitmap in the tablespace (LOCAL). In
addition, the extents can be AUTOALLOCATED, to enable the system to
manage them as to size; or the UNIFORM clause, with or without a
size specification, can be used to force all extents to a uniform
size. For versions earlier than 9i, you should not make the system
tablespace anything other than dictionary-managed.
CHARACTER_SET and NATIONAL_CHARACTER_SET.
For Oracle8, Oracle8i, and Oracle9i, determines the character set
that data will be stored in. This value is operating
system-dependent.
ARCHIVELOG and NOARCHIVELOG. If you need
archive logging, set ARCHIVELOG; if you don’t need it right away,
set NOARCHIVELOG. I suggest using NOARCHIVELOG to avoid creation of
multiple archive logs during initial database creation; you won’t
recover from a failed build, you will just rebuild. This is one
thing to check if the build seems to stall during later steps
(running catproc.sql, for example): the archive log location may
have filled. This is checked using the alert log stored in the
location specified by USER_DUMP_DESTINATION.
Databases are created in EXCLUSIVE mode, and
are either EXCLUSIVE or PARALLEL. A database must be altered to
PARALLEL mode after creation if you intend to use the oracle
parallel or RAC options.
The CHARACTER_SET is used for normal data.
Character specifications AF16UTF16, JA16SJISFIXED, JA16EUCFIXED, and
JA16DBCSFIXED can be used only as the NATIONAL_CHARACTER_SET. The
NATIONAL_CHARACTER_SET specifies the national character set used to
store data in columns specifically defined as NCHAR, NCLOB, or
NVARCHAR2. The NATIONAL_CHARACTER_SET is usually specified as
AF16UTF16 or UTF8 (formally known as UNICODE). You cannot change the
national character set after creating the database. If not
specified, the national character set defaults to the database
character set. There are nearly 300 character sets supported. For a
complete list, consult the Oracle9i Globalization Support Guide
Release 1 (9.0.1) Part Number A90236-01,June 2001, Oracle
Corporation.
See Code Depot
www.oracle-script.com |
