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Teach yourself Oracle8 in 21 day

when you are analyzing the system.
<H2><FONT COLOR="#000077">General</FONT></H2>
<P>These parameters are of a general nature; they typically set limits and do not
significantly affect performance--except that they might take up space in the SGA.
AQ_TM_PROCESS [0/1] &lt;0&gt; This parameter specifies whether a time manager is
created. If <TT>AQ_TM_PROCESS</TT> is set to <TT>1</TT>, a time-manager process is
created to monitor the messages. </P>

<P><B>ARCH_IO_SLAVES [0-15] &lt;0&gt; <BR>
</B>The number of I/O slaves to be used by the ARCH process. This should be adjusted
if archiving is running into an I/O bottleneck. </P>

<P><B>BACKGROUND_CORE_DUMP [FULL/PARTIAL] &lt;FULL&gt; <BR>
</B>This parameter specifies whether the SGA is dumped as part of the generated core
file. </P>

<P><B>BACKGROUND_DUMP_DEST [pathname] &lt;OS dependent&gt; <BR>
</B>This parameter specifies the destination directory where the debugging trace
files for the background processes are written. The background processes log all
startup and shutdown messages and errors to these files, as well as any other error
logs. A log of all <TT>CREATE</TT>, <TT>ALTER</TT>, or <TT>DROP</TT> statements is
also stored here. </P>

<P><B>BLANK_TRIMMING [TRUE/FALSE] &lt;FALSE&gt; <BR>
</B>If the value of <TT>BLANK_TRIMMING</TT> is <TT>TRUE</TT>, this allows a data
assignment of a string variable to a column value that is smaller (assuming that
the truncated characters are blank). </P>

<P><B>CHECKPOINT_PROCESS [TRUE/FALSE] &lt;FALSE&gt; <BR>
</B>This parameter determines whether the CKPT background process is enabled. During
a checkpoint, the headers of all the datafiles must be updated. This task is usually
performed by the LGWR process. Writing the blocks to disk is the job of the DBWR
process. If you notice that the LGWR is slowing down during checkpoints, it might
be necessary to enable CKPT to eliminate the extra work that LGWR is doing. </P>

<P><B>CLEANUP_ROLLBACK_ENTRIES [number] &lt;20&gt; <BR>
</B>This parameter specifies the number of undo records processed at a time when
a rollback occurs. This breaks up the rollback and limits a large rollback from locking
out smaller rollbacks. </P>

<P><B>CLOSE_CACHED_OPEN_CURSORS [TRUE/FALSE] &lt;FALSE&gt; <BR>
</B>This parameter specifies whether cursors that have been opened and cached by
PL/SQL are automatically closed at <TT>COMMIT</TT>. A value of <TT>FALSE</TT> allows
these cursors to remain open for further use. If cursors are rarely reused, you can
save space in the SGA by setting this value to <TT>TRUE</TT>. If cursors are reused,
you can improve performance by leaving this parameter at the default value of <TT>FALSE</TT>.
</P>

<P><B>COMPATIBLE [variable] &lt;release dependent&gt; <BR>
</B>Setting this variable guarantees that the DBMS will remain compatible with the
specified release. Some features might have to be limited for the compatibility to
be maintained. </P>

<P><B>COMPATIBLE_NO_RECOVERY [variable] &lt;release dependent&gt; <BR>
</B>This parameter works like the <TT>COMPATIBLE</TT> parameter except that the earlier
version (specified as the parameter) might not work on the current database if recovery
is necessary. </P>

<P><B>CONTROL_FILE_RECORD_KEEP_TIME [0-365] &lt;7&gt; <BR>
</B>This parameter specifies the minimum age (in days) that a record in the control
file must be kept before it can be reused. </P>

<P><B>CONTROL_FILES [1..8 filenames] &lt;OS dependent&gt; <BR>
</B>This parameter specifies the path names of one to eight control files. It is
recommended that there always be more than one control file and that they exist on
different physical devices. </P>

<P><B>CORE_DUMP_DEST [directory name] &lt;ORACLE_HOME/DBS/&gt; <BR>
</B>This parameter specifies the directory where core files are dumped. </P>

<P><B>DB_DOMAIN [extension components of a global db name] &lt;WORLD&gt; <BR>
</B>This parameter specifies the extension components of the global database name
consisting of valid identifiers separated by periods (for example, <TT>texas.us.widgets.com</TT>).
This allows multiple divisions to each have an <TT>ACCOUNTING</TT> database that
is uniquely identified by the addition of the domain. </P>

<P><B>DBLINK_ENCRYPT_LOGIN [TRUE/FALSE] &lt;FALSE&gt; <BR>
</B>When you connect to another server, Oracle encrypts the password. If the value
of <TT>DBLINK_ENCRYPT_LOGIN</TT> is <TT>FALSE</TT> and the connection fails, Oracle
tries to connect again with a nonencrypted password. If <TT>DBLINK_ENCRYPT_LOGIN</TT>
is <TT>TRUE</TT> and the connection fails, Oracle does not attempt to reconnect.
</P>

<P><B>DB_FILES [min: MAXDATAFILES, max OS dependent] &lt;OS dependent&gt; <BR>
</B>This parameter specifies the maximum number of database files that can be open.
This value can be reduced if you want to reclaim space in the SGA. No performance
degradation is incurred by leaving this value high, just additional memory usage
in the SGA. </P>

<P><B>DB_FILE_DIRECT_IO_COUNT [OS Dependent] &lt;64&gt; <BR>
</B>This parameter specifies the number of blocks to be used for I/O operations done
by backup, restore, or direct path read/write functions. </P>

<P><B>DB_NAME [valid name] &lt;NULL&gt; <BR>
</B>This parameter provides a string of up to eight characters in length that specifies
the name of the database. The following characters are valid:

<UL>
	<LI>Alphabetic characters
	<P>
	<LI>Numbers
	<P>
	<LI>Underscore (_)
	<P>
	<LI>Pound sign (<TT>#</TT>)
	<P>
	<LI>Dollar sign (<TT>$</TT>)
</UL>

<P>No other characters can be used. Double quotation marks are removed and cannot
be part of the name. The characters used in the <TT>DB_NAME</TT> parameter are case
insensitive, so <TT>SALES</TT>, <TT>Sales</TT>, and <TT>sales</TT> are equal. </P>

<P><B>ENQUEUE_RESOURCES [10..65535] &lt;derived&gt; <BR>
</B>This parameter specifies the number of resources that can be locked by the lock
manager. The default value is derived from <TT>PROCESSES</TT> and is usually sufficient.
The value is derived from this formula:</P>
<PRE><FONT COLOR="#0066FF">PROCESSES &lt;= 3; default values = 20
PROCESSES 4-10; default value = ((PROCESSES -  3) * 5) + 20
PROCESSES &gt; 10; default value = ((PROCESSES - 10) * 2) + 55
</FONT></PRE>
<P>If you use a large number of tables, you might have to increase this value. This
value should never exceed <TT>DML_LOCKS</TT> + <TT>DDL_LOCKS</TT> + 20 (overhead).
</P>

<P><B>GLOBAL_NAMES [TRUE/FALSE] &lt;FALSE&gt; <BR>
</B>This parameter determines whether a database link is required to have the same
name as the database to which it connects. Oracle recommends setting this parameter
to <TT>TRUE</TT> to ensure the use of consistent naming conventions for databases
and links. </P>

<P><B>IFILE [parameter filename] &lt;NULL&gt; <BR>
</B>This parameter embeds another parameter file into the current parameter file.
This can be very useful to separate specific changes from the general changes that
you often make. The parameter also allows you to separate different types of parameters
such as parallel options. </P>

<P><B>INIT_SQL_FILES [SQL filename] &lt;NULL&gt; <BR>
</B>This parameter lists the names of SQL files that should be run immediately after
database creation. This parameter can be used to automatically create the data dictionary.
</P>

<P><B>JOB_QUEUE_INTERVAL [1..3600] &lt;60&gt; <BR>
</B>This parameter specifies, in seconds, the interval between wake-ups of the SNP
background process. The processes run jobs that have been queued. </P>

<P><B>JOB_QUEUE_KEEP_CONNECTIONS [1..10] &lt;0&gt; <BR>
</B>This parameter specifies the number of SNP background processes per instance.
</P>

<P><B>JOB_QUEUE_PROCESSES [TRUE/FALSE] &lt;FALSE&gt; <BR>
</B>This parameter specifies whether remote connections should be shut down after
remote jobs have finished executing. </P>

<P><B>LICENSE_MAX_SESSIONS [0..number of session licenses] &lt;0&gt; <BR>
</B><TT>LICENSE_MAX_USERS</TT> sets the maximum number of concurrent user sessions
allowed. When this limit is reached, only users with <TT>RESTRICTED SESSION</TT>
privilege can connect to the server. A zero value indicates that this constraint
is not enforced. Either <TT>LICENSE_MAX_USERS</TT> or <TT>LICENSE_MAX_SESSIONS</TT>
should be set, not both. </P>

<P><B>LICENSE_MAX_USERS [0..number of user licenses] &lt;0&gt; <TT><BR>
</TT></B><TT>LICENSE_MAX_USERS</TT> sets the maximum number of concurrent users that
can simultaneously access the database. When this limit is reached, no more user
sessions can be created. A zero value indicates that this constraint is not enforced.
Either <TT>LICENSE_MAX_USERS</TT> or <TT>LICENSE_MAX_SESSIONS</TT> should be set,
not both. </P>

<P><B>LICENSE_SESSIONS_WARNING [0..LICENSE_MAX_SESSIONS] &lt;0&gt; <BR>
</B>Sets a warning limit so that the administrator can be aware that the <TT>LICENSE_MAX_SESSIONS</TT>
limit might soon be reached. After <TT>LICENSE_SESSIONS_WARNING</TT> number of users
have connected, a message is written to the alert log for each additional user connecting.
</P>

<P><B>LOCAL_LISTENER [string] &lt;Listener Identifier&gt; <BR>
</B>This parameter identifies local Net8 listeners. </P>

<P><B>LOG_ARCHIVE_DEST [valid path or device name] &lt;OS dependent&gt; <BR>
</B>When running in <TT>ARCHIVELOG</TT> mode, this text value specifies the default
location and root of the file or tape device to use when archiving redo log files.
Archiving to tape is not supported under all operating systems. </P>

<P><B>LOG_ARCHIVE_DUPLEX_DEST [valid path] &lt;NULL&gt; <BR>
</B>This parameter specifies a second archive destination for duplexed archiving.
</P>

<P><B>LOG_ARCHIVE_FORMAT [valid filename] &lt;OS dependent&gt; <BR>
</B>This parameter uses a text string and variables to specify the default filename
format of the archive log files. This string is appended to the <TT>LOG_ARCHIVE_DEST</TT>
parameter name. The following variables can be used in the string:

<UL>
	<LI><TT>%s</TT>--Log sequence number.
	<P>
	<LI><TT>%t</TT>--Thread number. Using uppercase letters (<TT>%S</TT>, <TT>%T</TT>)
	causes the value to be fixed length, padded to the left with zeros. A good value
	is similar to the following:
</UL>



<BLOCKQUOTE>
	<PRE><FONT COLOR="#0066FF">LOG_ARCHIVE_FORMAT = `log%S_%T.arc'</FONT></PRE>

</BLOCKQUOTE>

<PRE><FONT COLOR="#0066FF"></FONT></PRE>
<P><B>LOG_ARCHIVE_MIN_SUCCEED_DEST [1..2] &lt;1&gt; <BR>
</B>This parameter specifies the minimum number of archive log destinations that
must succeed. </P>

<P><B>LOG_ARCHIVE_START [TRUE/FALSE] &lt;FALSE&gt; <BR>
</B>When running in <TT>ARCHIVELOG</TT> mode, <TT>LOG_ARCHIVE_START</TT> specifies
whether archiving should be started up automatically at instance startup. A setting
of <TT>TRUE</TT> indicates that archiving is automatic; <TT>FALSE</TT> indicates
that archiving is manual. </P>

<P><B>LOG_BLOCK_CHECKSUM [TRUE/FALSE] &lt;FALSE&gt; <BR>
</B>Setting this parameter to <TT>TRUE</TT> causes each log block to be given a checksum.
This checksum is written into the header of each block. </P>

<P><B>LOG_CHECKPOINTS_TO_ALERT [TRUE/FALSE] &lt;FALSE&gt; <BR>
</B>This parameter specifies whether you want to log the checkpoints to the alert
log. This can be useful in verifying the frequency of checkpoints. </P>

<P><B>LOG_FILES [2..255] &lt;255&gt; <BR>
</B>This parameter specifies the maximum number of redo log files that can be opened
at instance startup. Reducing this value can save some space in the SGA. If this
value is set higher than the value of <TT>MAXLOGFILES</TT> used at database creation,
it does not override <TT>MAXLOGFILES</TT>. </P>

<P><B>MAX_DUMP_FILE_SIZE [0..unlimited] &lt;500 blocks&gt; <BR>
</B>This parameter specifies the maximum size in OS blocks of any trace file written.
Set this if you are worried that trace files might consume too much space. MAX_ENABLED_ROLES
[0..48] &lt;20&gt; This parameter specifies the maximum number of database roles
(including subroles) that a user can enable. </P>

<P><B>MAX_ROLLBACK_SEGMENTS [1..65536] &lt;30&gt; <BR>
</B>This parameter specifies the maximum number of rollback segments that can be
online for one instance. </P>