This lists the Oracle tuning parameters, grouping them into general areas of use and then sorting them alphabetically within the group. The section headings are the syntax for the parameters. The syntax contains information in the following format:
PARAMETER [option1, option2, option3, etc..] <DEFAULT VALUE>
A value that is italicized indicates that the value should be replaced with one of your own. A value that is italicized and in CAPS indicates a choice of this keyword. The / character indicates an OR condition. A value enclosed in brackets (<>) indicates the default value for that parameter.
These parameters are divided into sections based on whether the parameter affects performance, enables system analysis, is a general parameter, and so on. There might be some overlap, so if a parameter is not in the section you expected, keep looking.
These parameters change the performance characteristics of the system.
ALWAYS_ANTI_JOIN [NESTED_LOOPS/MERGE/ HASH] <NESTED_LOOPS> This parameter sets the type of anti-join that the Oracle server uses. This specifies the algorithm chosen for the anti-join.
B_TREE_BITMAP_PLANS [TRUE/FALSE] <FALSE>
When set to TRUE, the optimizer considers a bitmap access path even
though a table might have only a regular B*-tree index.
BITMAP_MERGE_AREA_SIZE [System Dependent] <1MB>
This parameter specifies the amount of memory used to merge bitmaps retrieved
from a range scan of the index. Larger values typically improve performance.
CLOSE_CACHED_OPEN_CURSORS [TRUE/FALSE] <FALSE>
This parameter specifies whether cursors opened and cached in memory are
automatically closed at each commit. If you frequently use cursors, this should
be set to FALSE.
CPU_COUNT [0-unlimited] <Automatic>
This parameter specifies the number of CPUs used by Oracle. This parameter is
set automatically and should not be changed.
CREATE_BITMAP_AREA_SIZE [OS Dependent] <8MB>
This parameter specifies the amount of memory to be used for bitmap creation. A
larger value might provide greater bitmap-creation performance. If the
cardinality is small, this number can be small.
CURSOR_SPACE_FOR_TIME [TRUE/FALSE] <FALSE>
CURSOR_SPACE_FOR_TIME causes the system to use more space for cursors, thus
increasing performance. This parameter affects both the shared SQL areas and the
user's private SQL area. This parameter speeds performance but uses more memory.
If CURSOR_SPACE_FOR_TIME is TRUE, the shared SQL areas remain pinned in the shared pool as long as an open cursor references them. This parameter should be used only if you have a sufficiently large shared pool to simultaneously hold all the processes' cursors.
The user's private SQL area is also retained during cursor execution, thus saving time and I/Os at the expense of memory. DB_BLOCK_BUFFERS [4..65535] <32 buffers> This parameter controls the number of database block buffers in the SGA. DB_BLOCK_BUFFERS is probably the most significant instance tuning parameter because the majority of I/Os in the system are generated by database blocks. Increasing DB_BLOCK_BUFFERS increases performance at the expense of memory. You can calculate the amount of memory that will be consumed with the following formula:
Buffer size = DB_BLOCK_BUFFERS * DB_BLOCK_SIZE
A larger number of database block buffers in the system creates a higher cache-hit rate, thus reducing the amount of utilized I/O and CPU and improving performance.
DB_BLOCK_CHECKPOINT_BATCH [0..derived] <8>
This parameter specifies the number of blocks that the DBWR writes in one batch
when performing a checkpoint. Setting this value too high causes the system to
flood the I/O devices during the checkpoint, severely degrades performance, and
increases response times--maybe to unacceptable levels.
You should set DB_BLOCK_CHECKPOINT_BATCH to a level that allows a checkpoint to finish before the next checkpoint occurs. Setting DB_BLOCK_CHECKPOINT_BATCH to 0 causes the default value of 8 to be used.
DB_BLOCK_SIZE [1024..8192 (OS dependent)] <OS dependent>
This parameter specifies in bytes the size of the Oracle database blocks. The
typical values are 2048 and 4096. If you set the block size relative to the size
of the rows in a database, you can reduce I/O. In some types of applications in
which large amounts of sequential accesses are performed, a larger database
block size can be beneficial. This value is useful only at database-creation
time.
DB_FILE_MULTIBLOCK_READ_COUNT [number (OS dependent)] <OS dependent>
DB_FILE_MULTIBLOCK_READ_COUNT specifies the maximum number of blocks
read in one I/O during a sequential scan. The default is a function of DB_BLOCK_BUFFERS
and PROCESSES. Reasonable values are 4, 16, or 32. The maximum allowed
values are OS dependent.
This parameter can be especially useful if you perform a large number of table scans, such as in a DSS system.
DB_FILE_SIMULTANEOUS_WRITES [1..24] <4>
This parameter specifies the number of simultaneous writes for each database
file when written by the DBWR. For disk arrays that handle large numbers of
requests in the hardware simultaneously, it is advantageous to set DB_FILE_SIMULTANEOUS_WRITES
to its maximum.
DISCRETE_TRANSACTIONS_ENABLED [TRUE/FALSE] <FALSE>
This parameter implements a simpler, faster rollback mechanism that, under
certain conditions, can improve performance. You can obtain greater efficiency
in this mode, but the qualification criteria for what kind of transactions can
take advantage of discrete transactions are quite strict.
DISK_ASYNCH_IO [TRUE/FALSE] <TRUE>
This parameter specifies that I/O to datafiles, control files, and log files are
asynchronous. This should be left enabled and not altered.
DML_LOCKS [20..unlimited,0] <4 * TRANSACTIONS>
This parameter specifies the maximum number of DML locks. A DML lock is used for
each table-modification transaction. DML locks are used in the DROP TABLE,
CREATE INDEX, and LOCK TABLE IN EXCLUSIVE MODE statements. If
the value is set to 0, enqueues (Oracle locking mechanisms) are
disabled, which improves performance slightly.
DBWR_IO_SLAVES [0..OS Dependent] <0>
This parameter specifies the number of I/O slaves used by the DBWR process.
HASH_AREA_SIZE [0..OS Dependent] <2*SORT_AREA_SIZE>
This parameter specifies the maximum amount of memory to be used for hash joins.
HASH_MULTIBLOCK_IO_COUNT [OS Dependent] <1>
This parameter specifies how many sequential blocks a hash join reads and writes
in one I/O.
LARGE_POOL_MIN_ALLOC [16K-64KB] <16KB>
This parameter specifies the minimum allocation size from the large pool. LARGE_POOL_SIZE
[300K or LARGE_POOL_MIN_ALLOC, whichever is larger] <0>
This parameter specifies the size of the large pool allocation heap.
LGWR_IO_SLAVES [0..OS Dependent] <0>
This parameter specifies the number of I/O slaves used by the LGWR process.
LOG_ARCHIVE_BUFFER_SIZE [1..OS Dependent] <OS dependent>
When running in ARCHIVELOG mode, this parameter specifies the size of
each archival buffer in redo log blocks. This parameter can be used in
conjunction with the LOG_ARCHIVE_BUFFERS parameter to make the
archiving speed faster or slower to affect overall system performance.
LOG_ARCHIVE_BUFFERS [1..OS Dependent] <OS dependent>
When running in ARCHIVELOG mode, this parameter specifies the number of
buffers to allocate to archiving. This parameter is used with the LOG_ARCHIVE_BUFFER_SIZE
parameter to control the speed of archiving.
LOG_BUFFER [OS Dependent] <OS dependent>
LOG_BUFFER specifies the number of bytes allocated to the redo log buffer.
Larger values reduce I/Os to the redo log by writing fewer blocks of a larger
size. This might help performance, particularly in a heavily used system.
LOG_CHECKPOINT_INTERVAL [2..unlimited] <OS dependent>
This parameter specifies the number of redo log file blocks to be filled to
cause a checkpoint to occur. Remember that a checkpoint always happens when a
log switch occurs. This parameter can be used to cause checkpoints to occur more
frequently. Sometimes, frequent checkpoints have less effect on the system than
one large checkpoint when the log switch occurs.
LOG_CHECKPOINT_TIMEOUT [0..unlimited] <OS dependent>
This parameter specifies the maximum amount of time that can pass before another
checkpoint must occur. This parameter can also be used to increase the frequency
of the checkpoint process, thus changing the overall system effect.
LOG_SIMULTANEOUS_COPIES [0..unlimited] <CPU_COUNT>
LOG_SIMULTANEOUS_COPIES specifies the number of redo buffer copy
latches simultaneously available to write log entries. You can have up to two
redo copy latches per CPU. This helps the LGWR process keep up with the extra
load generated by multiple CPUs.
If this parameter is 0, redo copy latches are turned off and all log entries are copied on the redo allocation latch.
LOG_SMALL_ENTRY_MAX_SIZE [number (OS dependent)] <OS dependent>
This parameter specifies the size in bytes of the largest copy to the log
buffers that can occur under the redo allocation latch without obtaining the
redo buffer copy latch. If LOG_SIMULTANEOUS_COPIES is zero, this
parameter is ignored.
OPTIMIZER_MODE [RULE/COST/FIRST_ROWS/ALL_ROWS] COST
When set to RULE, this parameter causes rule-based optimization to be
used, unless hints are supplied in the query. When set to COST, this
parameter causes a cost-based approach for the SQL statement, providing that
there are any statistics in the data dictionary. When set to FIRST_ROWS,
the optimizer chooses execution plans that minimize response time. When set to ALL_ROWS,
the optimizer chooses execution plans that minimize total execution time.
OPTIMIZER_PERCENT_PARALLEL [0..100] <0>
This parameter specifies the amount of parallelism the optimizer uses in its
cost functions.
OPTIMIZER_SEARCH_LIMIT <5>
This parameter specifies the search limit for the optimizer.
PRE_PAGE_SGA [TRUE/FALSE] <FALSE>
When set to TRUE, this parameter specifies that at instance startup all
pages of the SGA are touched, causing them to be allocated in memory. This
increases startup time but reduces page faults during runtime. This is useful if
you have a large number of processes starting at once. This parameter can
increase the system performance in that case by avoiding memory-allocation
overhead.
ROLLBACK_SEGMENTS [Any rollback segment names] <NULL>
ROLLBACK_SEGMENTS specifies one or more rollback-segment names to
be allocated to this instance. If ROLLBACK_SEGMENTS is not specified,
the public rollback segments are used. If you want to move your rollback
segments to a different disk device, you must specify it here. The parameter is
specified as follows:
ROLLBACK_SEGMENTS = (roll1, roll2, roll3)
If you use the Oracle Parallel Server option, you must name different rollback segments for each instance.
ROW_CACHE_CURSORS [10..3300] <10>
This parameter specifies the number of cached recursive cursors used by the row
cache manager for selecting rows from the data dictionary. The default is
usually sufficient unless you have particularly high access to the data
dictionary.
ROW_LOCKING [ALWAYS/INTENT] <ALWAYS>
The value ALWAYS specifies that only row locks are acquired when a
table is updated. If you set this value to INTENT, row locks are
acquired on a SELECT FOR UPDATE, but when the update occurs, a table
lock is acquired. SEQUENCE_CACHE_ENTRIES [10..32000] <10> This parameter
specifies the number of sequences that can be cached in the SGA. By caching the
sequences, an immediate response is achieved for sequences. Set a large value
for SEQUENCE_CACHE_ENTRIES if you have a high concurrency of processes
requesting sequences.
SEQUENCE_CACHE_HASH_BUCKETS [1..32000 (prime number)] <7>
This parameter specifies the number of buckets to speed up access to sequences
in the cache. The cache is arranged as a hash table.
SERIAL_REUSE [DISABLE/SELECT/DML/PLSQL/ALL/NULL] <NULL>
This parameter specifies which type of SQL cursors should make use of
serial-reusable memory.
SERIALIZABLE [TRUE/FALSE] <FALSE>
If this value is set to TRUE, queries obtain table-level read
locks, which prohibits other transactions from modifying that table until the
transaction has committed or rolled back the transaction. This mode provides
repeatable reads and ensures that within the transactions multiple queries to
the same data achieve the same result.
With SERIALIZABLE set to TRUE, degree-three consistency is provided. You pay a performance penalty when you run in this mode. Running in this mode is usually not necessary.
SESSION_CACHED_CURSORS [0..OS dependent] <0>
This parameter specifies the number of session cursors to cache. If parse
calls of the same SQL statement are repeated, this can cause the session cursor
for that statement to be moved into the session cursor cache. Subsequent calls
need not reopen the cursor.
SESSION_MAX_OPEN_FILES [1..MAX_OPEN_FILES] <10>
This parameter specifies the maximum number of BFILEs that can be
opened by any given session. The BFILE stores unstructured binary data
in OS files outside the database.
SHARED_POOL_RESERVED_MIN_ALLOC [5000..SHARED_POOL_RESERVE_SIZE]
<5000>
Memory allocations larger than this value cannot allocate space from the
reserved list.
SHARED_POOL_RESERVE_SIZE [SHARED_POOL_RESERVE_MIN_ALLOC..
(SHARED_POOL_SIZE/2)] <5% of SHARED_POOL_SIZE>
This parameter specifies the shared pool space that is reserved for large
contiguous requests for shared-pool memory.
SHARED_POOL_SIZE [300KB..OS dependent] <3.5MB>
This parameter specifies the size of the shared pool in bytes. The shared
pool contains the data dictionary cache (row cache) and the library cache as
well as session information. Increasing the size of the shared pool should help
performance, but at the cost of memory.
SMALL_TABLE_THRESHOLD [0..OS dependent] <4>
This parameter specifies the number of buffers available in the SGA for
table scans. A small table might be read entirely into cache if it fits in SMALL_TABLE_THRESHOLD
number of buffers. When scanning a table larger than this, these buffers are
reused immediately. This provides a mechanism to prohibit a single-table scan
from taking over the buffer cache.
SORT_AREA_RETAINED_SIZE [0..SORT_AREA_SIZE] <SORT_AREA_SIZE>
SORT_AREA_RETAINED_SIZE defines the maximum amount of session
memory in bytes that can be used for an in-memory sort. The memory is released
when the last row is fetched from the sort area.
If the sort does not fit in SORT_AREA_RETAINED_SIZE bytes, a temporary segment is allocated and the sort is performed in this temporary table. This is called an external (disk) sort. This value is important if sort performance is critical. SORT_AREA_SIZE [number of bytes] <OS dependent> This value specifies the maximum amount of PGA memory to use for an external sort. This memory is released when the sorted rows are written to disk. Increasing this value increases the performance of large sorts.
Remember that each user process has its own PGA. You can calculate the potential memory usage if all the users are doing a large sort with the following formula:
Potential memory usage = SORT_AREA_SIZE * (number of users doing a large sort)
If very large indexes are being created, you might want to increase the value of this parameter. SORT_SPACEMAP_SIZE [bytes] <OS dependent> This parameter specifies the size in bytes of the sort spacemap in the context area. If you have very large indexes, increase the value of this parameter. Optimal performance is achieved when this parameter has the following value:
SORT_SPACEMAP_SIZE = (total-sort-bytes / sort-area-size) + 64
In this formula, total-sort-bytes has the following value:
total-sort-bytes = record-count * ( sum-of-average-column-sizes + ( 2 * number-of-columns ) )
number-of-columns includes the SELECT list for ORDER BY, GROUP BY, and the key list for the CREATE INDEX. You should also add 10 or 20 extra bytes for overhead.
SORT_WRITE_BUFFER_SIZE [32KB/64KB] <32768>
This parameter specifies the size of the sort I/O buffer when SORT_DIRECT_WRITES
is set to TRUE.
SORT_WRITE_BUFFERS [2..8] <1>
This parameter specifies the number of sort buffers when SORT_DIRECT_WRITES
is set to TRUE.
SPIN_COUNT [1..1,000,000] <1>
This parameter specifies the number of times to spin on a latch before
sleeping.
STAR_TRANSFORMATION_ENABLED [TRUE/FALSE] <FALSE>
This parameter specifies whether a cost-based query transformation will be
applied to star queries.
USE_ISM [TRUE/FALSE] <TRUE>
This parameter specifies that the shared page table is enabled.
The following parameters affect the operation of the Parallel Query option, which has been available in Oracle since version 7.1. The Parallel Query option can dramatically affect the performance of certain operations.
PARALLEL_DEFAULT_MAX_SCANS [0..unlimited] <OS dependent>
This value specifies the maximum number of query servers to be used by
default for a query. This valued is used only if there are no values specified
in a PARALLEL hint or in the PARALLEL definition clause. This
limits the number of query servers used by default when the value of PARALLEL_DEFAULT_SCANSIZE
is used by the query coordinator.
PARALLEL_DEFAULT_SCANSIZE [0..OS Dependent ] <OS dependent>
This parameter is used to determine the number of query servers to be used
for a particular table. The size of the table divided by PARALLEL_DEFAULT_SCANSIZE
determines the number of query servers, up to PARALLEL_DEFAULT_MAX_SCANS.
PARALLEL_MAX_SERVERS [0..100] <OS dependent>
This parameter specifies the maximum number of query servers or parallel
recovery processes available for this instance.
PARALLEL_MIN_MESSAGE_POOL [0..(SHARED_POOLSIZE*.9)] <equation>
This parameter specifies the minimum permanent amount of memory that will be
allocated from the shared pool for messages in parallel execution.
PARALLEL_MIN_PERCENT [0..100] <0>
This parameter specifies the minimum percent of threads required for
parallel query.
PARALLEL_MIN_SERVERS [0..PARALLEL_MAX_SERVERS] <0>
This parameter determines the minimum number of query servers for an
instance. It is also the number of query servers started at instance startup.
PARALLEL_SERVER_IDLE_TIME [0..unlimited] <OS dependent>
This parameter specifies the number of minutes before Oracle terminates an
idle query server process.
RECOVERY_PARALLELISM [0..PARALLEL_MAX_SERVERS] <OS dependent>
This parameter specifies the number of processes to be used for instance or
media recovery. A large value can greatly reduce instance recovery time. A value
of 0 or 1 indicates that parallel recovery will not be
performed and that recovery will be serial.
These parameters turn on special features in Oracle for detailed analysis and debugging.
DB_BLOCK_CHECKSUM [TRUE/FALSE] <FALSE>
Setting this parameter to TRUE causes the DBWR and direct loader to
calculate a checksum for every block they write to disk. This checksum is
written into the header of each block.
DB_LOG_CHECKSUM [TRUE/FALSE] <FALSE>
Setting this parameter to TRUE causes the LGWR to calculate a
checksum for every block it writes to disk. The checksum is written into the
header of the redo block.
DB_BLOCK_LRU_EXTENDED_STATISTICS [0..unlimited] <0>
This parameter enables statistics in the X$KCBRBH table to be
gathered. These statistics estimate the increased number of database block
buffer cache hits for each additional buffer. Any value over zero specifies the
number of buffers to estimate the cache hits for. If you are interested in
estimating the cache hits for an additional 100 buffers, set this parameter to 100.
This parameter affects performance and should be turned off during normal operation.
DB_BLOCK_LRU_LATCHES [1.. number of CPUs] <CPU_COUNT/2>
This parameter specifies the upper bound of the number of LRU latch sets.
This is the number of LRU latch sets that you want. Oracle decides whether to
use this number or a smaller one.
DB_BLOCK_LRU_STATISTICS [TRUE/FALSE] <FALSE>
This parameter specifies whether statistics are gathered for database block
buffer cache hit estimates as specified in DB_BLOCK_LRU_EXTENDED_STATISTICS.
Set this parameter to TRUE when you want to gather these statistics.
DB_BLOCK_MAX_DIRTY_TARGET [100..all buffers or 0] <all buffers>
This parameter specifies the number of buffers that can be dirty. If the
number of dirty buffers exceeds this, the DBWR writes out buffers to reduce the
number of dirty buffers.
EVENT <NULL>
The EVENT parameter modifies the scope of ALTER SESSION SET
EVENTS commands so that they pertain to the entire instance rather than
just the session. This is an Oracle internal parameter and should be changed
only at the direction of Oracle support.
FIXED_DATE [date string] <NULL>
FIXED_DATE allows you to set as a constant the Oracle function SYSDATE
in the format YYYY-MM-DD-HH24:MI:SS. Use this parameter for debug only. This
parameter allows you to test your application's functionality with certain
dates, such as the turn of the century.
ORACLE_TRACE_COLLECTION_NAME [valid name] <NULL>
This parameter specifies the Oracle Trace collection name.
ORACLE_TRACE_COLLECTION_PATH [valid path] <NULL>
This parameter specifies the directory where Oracle Trace collection
definition and datafiles are located.
ORACLE_TRACE_COLLECTION_SIZE [0..4294967295] <5242880>
The maximum size in bytes of the Oracle Trace collection file.
ORACLE_TRACE_ENABLE [TRUE/FALSE] <FALSE>
Enables Oracle Trace collections for the server.
ORACLE_TRACE_FACILITY_NAME [valid name] <OS Specific>
This parameter specifies the name of the Oracle Trace product definition
file.
ORACLE_TRACE_FACILITY_PATH [valid directory name] <OS Specific>
This parameter specifies the directory where the Oracle Trace facility
definition files are located.
SQL_TRACE [TRUE/FALSE] <FALSE>
This parameter specifies whether the SQL*Trace facility is enabled. The
SQL*Trace facility can provide valuable information but at the price of some
overhead. Use SQL*Trace only when you are tracking down a specific problem.
SORT_READ_FAC [integer] <OS Dependent>
SORT_READ_FAC defines a unitless ratio that describes the
amount of time to read a single database block divided by the block transfer
rate.
TIMED_OS_STATISTICS [OFF/CALL/LOGOFF] <OFF>
This parameter allows the system administrator to gather OS statistics when
calls are pushed or popped or when a user logs off.
TIMED_STATISTICS [TRUE/FALSE] <FALSE>
When TIMED_STATISTICS is set to TRUE, the time-related
statistics in the dynamic performance tables are enabled. This information can
be quite useful, but there is considerable overhead involved. Only enable TIMED_STATISTICS
when you are analyzing the system.
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] <0> This parameter specifies whether a time manager is created. If AQ_TM_PROCESS is set to 1, a time-manager process is created to monitor the messages.
ARCH_IO_SLAVES [0-15] <0>
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.
BACKGROUND_CORE_DUMP [FULL/PARTIAL] <FULL>
This parameter specifies whether the SGA is dumped as part of the generated
core file.
BACKGROUND_DUMP_DEST [pathname] <OS dependent>
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 CREATE, ALTER, or DROP
statements is also stored here.
BLANK_TRIMMING [TRUE/FALSE] <FALSE>
If the value of BLANK_TRIMMING is TRUE, this allows a data
assignment of a string variable to a column value that is smaller (assuming that
the truncated characters are blank).
CHECKPOINT_PROCESS [TRUE/FALSE] <FALSE>
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.
CLEANUP_ROLLBACK_ENTRIES [number] <20>
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.
CLOSE_CACHED_OPEN_CURSORS [TRUE/FALSE] <FALSE>
This parameter specifies whether cursors that have been opened and cached by
PL/SQL are automatically closed at COMMIT. A value of FALSE
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 TRUE. If
cursors are reused, you can improve performance by leaving this parameter at the
default value of FALSE.
COMPATIBLE [variable] <release dependent>
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.
COMPATIBLE_NO_RECOVERY [variable] <release dependent>
This parameter works like the COMPATIBLE parameter except that the
earlier version (specified as the parameter) might not work on the current
database if recovery is necessary.
CONTROL_FILE_RECORD_KEEP_TIME [0-365] <7>
This parameter specifies the minimum age (in days) that a record in the
control file must be kept before it can be reused.
CONTROL_FILES [1..8 filenames] <OS dependent>
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.
CORE_DUMP_DEST [directory name] <ORACLE_HOME/DBS/>
This parameter specifies the directory where core files are dumped.
DB_DOMAIN [extension components of a global db name] <WORLD>
This parameter specifies the extension components of the global database
name consisting of valid identifiers separated by periods (for example, texas.us.widgets.com).
This allows multiple divisions to each have an ACCOUNTING database that
is uniquely identified by the addition of the domain.
DBLINK_ENCRYPT_LOGIN [TRUE/FALSE] <FALSE>
When you connect to another server, Oracle encrypts the password. If the
value of DBLINK_ENCRYPT_LOGIN is FALSE and the connection
fails, Oracle tries to connect again with a nonencrypted password. If DBLINK_ENCRYPT_LOGIN
is TRUE and the connection fails, Oracle does not attempt to reconnect.
DB_FILES [min: MAXDATAFILES, max OS dependent] <OS dependent>
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.
DB_FILE_DIRECT_IO_COUNT [OS Dependent] <64>
This parameter specifies the number of blocks to be used for I/O operations
done by backup, restore, or direct path read/write functions.
DB_NAME [valid name] <NULL>
This parameter provides a string of up to eight characters in length that
specifies the name of the database. The following characters are valid:
No other characters can be used. Double quotation marks are removed and cannot be part of the name. The characters used in the DB_NAME parameter are case insensitive, so SALES, Sales, and sales are equal.
ENQUEUE_RESOURCES [10..65535] <derived>
This parameter specifies the number of resources that can be locked by the
lock manager. The default value is derived from PROCESSES and is
usually sufficient. The value is derived from this formula:
PROCESSES <= 3; default values = 20 PROCESSES 4-10; default value = ((PROCESSES - 3) * 5) + 20 PROCESSES > 10; default value = ((PROCESSES - 10) * 2) + 55
If you use a large number of tables, you might have to increase this value. This value should never exceed DML_LOCKS + DDL_LOCKS + 20 (overhead).
GLOBAL_NAMES [TRUE/FALSE] <FALSE>
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 TRUE to ensure the use of consistent naming conventions
for databases and links.
IFILE [parameter filename] <NULL>
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.
INIT_SQL_FILES [SQL filename] <NULL>
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.
JOB_QUEUE_INTERVAL [1..3600] <60>
This parameter specifies, in seconds, the interval between wake-ups of the
SNP background process. The processes run jobs that have been queued.
JOB_QUEUE_KEEP_CONNECTIONS [1..10] <0>
This parameter specifies the number of SNP background processes per
instance.
JOB_QUEUE_PROCESSES [TRUE/FALSE] <FALSE>
This parameter specifies whether remote connections should be shut down
after remote jobs have finished executing.
LICENSE_MAX_SESSIONS [0..number of session licenses] <0>
LICENSE_MAX_USERS sets the maximum number of concurrent user
sessions allowed. When this limit is reached, only users with RESTRICTED
SESSION privilege can connect to the server. A zero value indicates that
this constraint is not enforced. Either LICENSE_MAX_USERS or LICENSE_MAX_SESSIONS
should be set, not both.
LICENSE_MAX_USERS [0..number of user licenses] <0>
LICENSE_MAX_USERS 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 LICENSE_MAX_USERS or LICENSE_MAX_SESSIONS
should be set, not both.
LICENSE_SESSIONS_WARNING [0..LICENSE_MAX_SESSIONS] <0>
Sets a warning limit so that the administrator can be aware that the LICENSE_MAX_SESSIONS
limit might soon be reached. After LICENSE_SESSIONS_WARNING number of
users have connected, a message is written to the alert log for each additional
user connecting.
LOCAL_LISTENER [string] <Listener Identifier>
This parameter identifies local Net8 listeners.
LOG_ARCHIVE_DEST [valid path or device name] <OS dependent>
When running in ARCHIVELOG 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.
LOG_ARCHIVE_DUPLEX_DEST [valid path] <NULL>
This parameter specifies a second archive destination for duplexed
archiving.
LOG_ARCHIVE_FORMAT [valid filename] <OS dependent>
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 LOG_ARCHIVE_DEST
parameter name. The following variables can be used in the string:
LOG_ARCHIVE_FORMAT = `log%S_%T.arc'
LOG_ARCHIVE_MIN_SUCCEED_DEST [1..2] <1>
This parameter specifies the minimum number of archive log destinations that
must succeed.
LOG_ARCHIVE_START [TRUE/FALSE] <FALSE>
When running in ARCHIVELOG mode, LOG_ARCHIVE_START
specifies whether archiving should be started up automatically at instance
startup. A setting of TRUE indicates that archiving is automatic; FALSE
indicates that archiving is manual.
LOG_BLOCK_CHECKSUM [TRUE/FALSE] <FALSE>
Setting this parameter to TRUE causes each log block to be given a
checksum. This checksum is written into the header of each block.
LOG_CHECKPOINTS_TO_ALERT [TRUE/FALSE] <FALSE>
This parameter specifies whether you want to log the checkpoints to the
alert log. This can be useful in verifying the frequency of checkpoints.
LOG_FILES [2..255] <255>
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 MAXLOGFILES used at
database creation, it does not override MAXLOGFILES.
MAX_DUMP_FILE_SIZE [0..unlimited] <500 blocks>
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] <20> This parameter specifies the maximum
number of database roles (including subroles) that a user can enable.
MAX_ROLLBACK_SEGMENTS [1..65536] <30>
This parameter specifies the maximum number of rollback segments that can be
online for one instance.
OBJECT_CACHE_MAX_SIZE_PERCENT [0%..OS Dependent] <10%>
This parameter specifies the percentage of the optimal cache size beyond
which the Session object cache size can grow.
OBJECT_CACHE_OPTIMAL_PERCENT [10KB..OS Dependent] <100KB>
This parameter specifies the optimal size of the Session object cache.
OPEN_CURSORS [1..OS limit] <50>
This parameter specifies the maximum number of open cursors that a single
user process can have open at once.
OPEN_LINKS [0..255] <4>
This parameter specifies the maximum number of concurrent open connections
to remote database processes per user process. This value should exceed the
maximum number of remote systems accessed within any single SQL statement.
PARTITION_VIEW_ENABLED [TRUE/FALSE] <FALSE>
If set to TRUE, the optimizer skips unnecessary table accesses in a
partition view.
PLSQL_V2_COMPATIBILITY [TRUE/FALSE] <FALSE>
This parameter sets the compatibility level for PL/SQL.
PROCESSES [6 to OS dependent] <50>
This parameter specifies the maximum number of OS user processes that
connect to the Oracle instance. This number must take into account the
background processes and the login process that started the instance. Be sure to
add an extra six processes for the background processes.
REMOTE_DEPENDENCIES_MODE [TIMESTAMP/SIGNATURE] <TIMESTAMP>
This parameter specifies how dependencies on remote stored procedures are to
be handled by the database.
REMOTE_LOGIN_PASSWORDFILE [NONE/SHARED/EXCLUSIVE] <NONE>
This parameter specifies whether Oracle checks for a password file. A value
of NONE indicates that users are authenticated through the operating
system. A value of EXCLUSIVE indicates that the password file can be
used only by one database and can contain names other than SYS and INTERNAL.
Setting this parameter to SHARED allows more than one database to use
this password file, but only SYS and INTERNAL are recognized
by this password file.
REPLICATION_DEPENDENCY_TRACKING [TRUE/FALSE] <TRUE>
This parameter specifies that dependency tracking for read/write operations
to the database is turned on.
RESOURCE_LIMIT [TRUE/FALSE] <FALSE>
A value of FALSE disables the enforcement of resource limits such
as sessions, CPU time, and so on. This disables the enforcement of those limits
regardless of how they are set.
SESSIONS [number] <1.1 * PROCESSES>
This parameter specifies the total number of user and system sessions.
Because recursive sessions might occur, this number should be set slightly
higher than PROCESSES. DDL_LOCKS is derived from this
parameter.
SHADOW_CORE_DUMP [FULL/PARTIAL] <FULL>
This parameter specifies whether the SGA is included in core dumps.
SNAPSHOT_REFRESH_INTERVAL [1..3600] <60>
This parameter specifies the number of seconds between wake-ups for the
instance's snapshot refresh process.
SNAPSHOT_REFRESH_KEEP_CONNECTION [TRUE/FALSE] <FALSE>
This parameter specifies whether the snapshot refresh process should keep
remote connections after the refresh. If set to FALSE, the remote
database connections are closed after the refreshes occur.
SNAPSHOT_REFRESH_PROCESS [0..10] <0>
This parameter specifies the number of snapshot refresh processes per
instance. You must set this value to 1 or higher for automatic
refreshes. One snapshot refresh process is usually sufficient.
SINGLE_PROCESS [TRUE/FALSE] FALSE
If SINGLE_PROCESS is set to TRUE, the database instance is
brought up in a single-user mode. A value of FALSE indicates that the
database is brought up in a multiprocess mode.
TEMPORARY_TABLE_LOCKS [0..OS dependent] <SESSIONS>
TEMPORARY_TABLE_LOCKS specifies the number of temporary tables that
can be created in the temporary segment space. A temporary table lock is
required whenever a sort occurs that cannot be held in memory (that is, the sort
exceeds SORT_AREA_RETAINED_SIZE). If your application contains a large
number of ORDER BY clauses or if you perform a large number of index
sorts, you might want to increase this number.
TRANSACTIONS [number] <1.1 * PROCESSES>
This parameter specifies the maximum number of concurrent transactions in
the instance. The default value is greater than PROCESSES to provide
for recursive transactions. A larger value increases the size of the SGA. If you
increase the number of transactions allowed in the system, you might also want
to increase the number of rollback segments available.
TRANSACTIONS_PER_ROLLBACK_SEGMENT [1..OS dependent] <30>
This value specifies the maximum number of concurrent transactions allowed
per rollback segment. You can calculate the minimum number of rollback segments
enabled at startup with this formula:
Rollback Segments = TRANSACTIONS / TRANSACTIONS_PER_ROLLBACK_SEGMENT
Performance can be improved if there is less contention on rollback segments. In a heavily used system, you might want to reduce TRANSACTIONS_PER_ROLLBACK_SEGMENT to decrease this contention.
USER_DUMP_DEST [valid path name] <OS dependent>
USER_DUMP_DEST specifies the path to where the debugging trace
files are written.
UTL_FILE_DIR [valid directory]
This parameter specifies directories that are permitted for PL/SQL file I/O.
These parameters are used in conjunction with the Recovery Manager.
BACKUP_DISK_IO_SLAVES [0..15] <0>
This parameter defines the number of I/O slaves used by the Recovery Manager
to back up, copy, or restore.
BACKUP_TAPE_IO_SLAVES [TRUE/FALSE] <FALSE>
This parameter specifies whether I/O slaves are used by the Recovery Manager
for tape operations.
DB_FILE_NAME_CONVERT [string]
This parameter converts the filename of a new datafile on the primary
database to a filename on the standby database.
LOG_FILE_NAME_CONVERT [string]
This parameter converts the filename of a new log file on the primary
database to a filename on the standby database.
TAPE_ASYNCH_IO [TRUE/FALSE] <TRUE>
This parameter specifies that I/O to sequential devices are asynchronous.
This should be left enabled and not altered.
These parameters are used if you are using the multithreaded server process.
MTS_DISPATCHERS ["protocol, number"] <NULL>
This parameter specifies the configuration of the dispatcher process(es)
created at startup time. The value of this parameter is a quoted string of two
values separated by a comma. The values are the network protocol and the number
of dispatchers. Each protocol requires a separate specification. This parameter
can be specified multiple times. Here is an example of two dispatcher
definitions:
MTS_DISPATCHERS = "tcp, 2" MTS_DISPATCHERS = "ipx, 1"
MTS_LISTENER_ADDRESS [configuration] <NULL>
This parameter specifies the configuration of the listener process
addresses. There must be a listener process address for each protocol used in
the system. Addresses are specified as the SQL*Net description of the connection
address.
Because each connection is required to have its own address, this parameter might be specified several times. Here is an example:
MTS_LISTENER_ADDRESS = "(ADDRESS=(PROTOCOL=tcp)(HOST=hostname)(PORT=7002))" MTS_LISTENER_ADDRESS = "(ADDRESS=(PROTOCOL=ipx)()())"
MTS_MAX_DISPATCHERS [OS dependent] <5>
This parameter specifies the maximum number of dispatcher processes allowed
to run simultaneously.
MTS_MAX_SERVERS [OS dependent] <20>
This parameter specifies the maximum number of shared server processes
allowed to run simultaneously.
MTS_MULTIPLE_LISTENERS [TRUE/FALSE] <FALSE>
This parameter is obsolete.
MTS_RATE_LOG_SIZE
[DEFAULTS/EVENT_LOOPS/MESSAGES/SERVER_BUFFERS/CLIENT_BUFFERS/TOTAL_BUFFERS/IN_CONNECTS/OUT_CONNECTS/RECONNECTS]
<10>
This parameter specifies the sample size used to calculate dispatcher-rate
statistics.
MTS_RATE_SCALE
[DEFAULTS/EVENT_LOOPS/MESSAGES/SERVER_BUFFERS/CLIENT_BUFFERS/TOTAL_BUFFERS/IN_CONNECTS/OUT_CONNECTS/RECONNECTS]
<misc>
This parameter specifies the scale at which dispatcher-rate statistics are
reported.
MTS_SERVERS [OS dependent] <0>
This parameter specifies the number of server processes created at instance
startup.
MTS_SERVICE [name] <DB_NAME>
This parameter specifies the name of the service to be associated with the
dispatcher. Using this name in the CONNECT string allows users to
connect using the dispatcher. The name should be unique. Do not specify this
name in quotes. It is usually a good idea to make this name the same as the
instance name. Because the dispatcher is tried first, if it is not available,
the CONNECT string can still connect the user into the database through
a normal database connection.
These parameters are meaningful only when you use the distributed option.
COMMIT_POINT_STRENGTH [0..255] <OS dependent>
This value is used to determine the commit point site when executing a
distributed transaction. The site with the highest value for COMMIT_POINT_STRENGTH
is the commit point site. The site with the largest amount of critical data
should be the commit point site.
DISTRIBUTED_LOCK_TIMEOUT [1..unlimited] <60 seconds>
DISTRIBUTED_LOCK_TIMEOUT specifies, in seconds, how long
distributed transactions should wait for locked resources.
DISTRIBUTED_RECOVERY_CONNECTION_HOLD_TIME [1..1800] <200 seconds>
DISTRIBUTED_RECOVERY_CONNECTION_HOLD_TIME specifies, in seconds,
how long to hold a remote connection open after a distributed transaction fails.
A larger value holds the connection longer but also continues to use local
resources even though the connection might have been severed. Any value larger
than 1,800 seconds interferes with the reconnection and recovery background
processes and will never drop a failed connection.
DISTRIBUTED_TRANSACTIONS [0..TRANSACTIONS] <OS dependent>
DISTRIBUTED_TRANSACTIONS specifies the maximum number of
distributed transactions that the database can process concurrently. This value
cannot exceed the value of TRANSACTIONS. If you are having problems
with distributed transactions because network failures are causing many in-doubt
transactions, you might want to limit the number of distributed transactions.
If DISTRIBUTED_TRANSACTIONS is set to 0, no distributed transactions are allowed and the RECO process does not start at instance startup.
MAX_TRANSACTION_BRANCHES [1..32] <8>
This parameter controls the number of branches in a distributed transaction.
REMOTE_OS_AUTHENT [TRUE/FALSE] <FALSE>
If this parameter is set to TRUE, it allows authentication to
remote systems with the value of OS_AUTHENT_PREFIX.
REMOTE_OS_ROLES [TRUE/FALSE] <FALSE>
If this parameter is set to TRUE, it allows remote clients to have
their roles managed by the OS. If REMOTE_OS_ROLES is FALSE,
roles are managed and identified by the database for the remote system.
These parameters are used only in conjunction with the Oracle Parallel Server option.
ALLOW_PARTIAL_SN_RESULTS [TRUE/FALSE] <FALSE>
This parameter allows partial results to be returned on queries to global
performance tables even if a slave could not be allocated.
CACHE_SIZE_THRESHOLD [number] <0.1 * DB_BLOCK_BUFFERS>
This parameter specifies the maximum size of a cached partition table split
among the caches of multiple instances. If the partition is larger than this
value, the table is not split among the caches.
DELAYED_LOGGING_BLOCK_CLEANOUTS [TRUE/FALSE] <TRUE>
This parameter enables the delayed block cleanout feature. This can reduce
OPS pinging.
FREEZE_DB_FOR_FAST_INSTANCE_RECOVERY [TRUE/FALSE]
This parameter specifies that the entire database freeze in order to speed
recovery.
GC_DEFER_TIME [integer] <0>
This parameter specifies the time the server waits (in hundredths of a
second) before responding to a forced-write request for hot blocks.
GC_DB_LOCKS [0..unlimited] <0>
This parameter specifies the number of PCM locks allocated. The value of GC_DB_LOCKS
should be at least one greater than the sum of the locks specified with the
parameter GC_FILES_TO_LOCKS.
GC_FILES_TO_LOCKS [file_number=locks:filename=locks] <NULL>
This parameter supplies a list of filenames, each specifying how many locks
should be allocated for that file. Optionally, the number of blocks and the
value EACH can be added to further specify the allocation of the locks.
GC_LCK_PROCS [0..10] <1>
This parameter specifies the number of lock processes (LCK0 to LCK9) to
create for the instance. The default value of 1 is usually sufficient
unless an unusually high number of locks are occurring.
GC_RELEASABLE_LOCKS [0..DB_BLOCK_BUFFERS] <DB_BLOCK_BUFFERS>
This parameter allocates space for fine-grain locking.
GC_ROLLBACK_LOCKS [number] <20>
This parameter specifies the number of distributed locks available for each
rollback segment. The default value is usually sufficient.
GC_ROLLBACK_SEGMENTS [number] <20>
GC_ROLLBACK_SEGMENTS specifies the maximum number of rollback
segments systemwide. This includes all instances in the parallel server system,
including the SYSTEM rollback segment.
GC_SAVE_ROLLBACK_LOCKS [number] <20>
This parameter specifies the number of distributed locks reserved for
deferred rollback segments. These deferred rollback segments contain rollback
entries for segments taken offline.
GC_SEGMENTS [number] <10>
This parameter specifies the maximum number of segments that might have
space-management activities simultaneously performed by different instances.
GC_TABLESPACES [number] <5>
This parameter specifies the maximum number of tablespaces that can be
simultaneously brought online or offline.
INSTANCE_GROUPS [string]
This parameter assigns the current instance to this instance group.
INSTANCE_NUMBER [1..OS dependent] <Lowest Available Number>
This parameter specifies a unique number that maps the instance to a group
of free space lists.
LM_LOCKS [512..Limited by Instance Size] <12000>
This parameter specifies the number of locks that are configured for the
lock manager.
LM_PROCS [36..PROCESSES+instances+safety factor] <64+instances>
This parameter represents the number of the PROCESSES parameter
plus the number of instances.
LM_RESS [256..Limited by Instance Size] <6000>
This parameter controls the number of resources that can be locked by each
lock-manager process.
LOCK_NAME_SPACE [string]
This parameter specifies the name space that the distributed lock manager
(DLM) uses to generate lock names.
MAX_COMMIT_PROPAGATION_DELAY [0..90000] <90000>
This parameter specifies the maximum amount of time that can pass before the
SCN (System Change Number) is changed by the DBWR. This value helps in certain
conditions where the SCN might not be refreshed often enough because of a high
load from multiple instances.
OPEN_LINKS_PER_INSTANCE [0..UB4MAXVAL] <4>
This parameter specifies the maximum number of migratable open connections.
OPS_ADMIN_GROUP [group name] <all instances>
This parameter allows instances to be grouped for monitoring and
administration.
PARALLEL_DEFAULT_MAX_INSTANCES [0..instances] <OS dependent>
This parameter specifies the default number of instances to spit a table
among for parallel query processing. This value is used if the INSTANCES
DEFAULT is specified in the table/cluster definition.
PARALLEL_INSTANCE_GROUP [string] <group>
This parameter specifies the parallel instance group to be used for spawning
parallel query slaves.
PARALLEL_SERVER [TRUE/FALSE] <FALSE>
Setting this to TRUE enables the Parallel Server option.
PARALLEL_TRANSACTION_RESOURCE_TIMEOUT [0..OS Dependent] <300>
This parameter specifies the maximum amount of time (seconds) that can pass
before a session executing a parallel operation will time-out while waiting on a
resource held by another session. THREAD [0..max threads] <0> This
parameter specifies the number of the redo thread to be used by this instance.
Any number can be used, but the value must be unique within the cluster.
These parameters help set up system security; manipulate them to obtain the best mix of efficiency and security.
AUDIT_FILE_DEST [dir_name] <$ORACLE_HOME/RDBMS/AUDIT>
This parameter specifies the directory where audit files are stored.
AUDIT_TRAIL [NONE,DB,OS]
The AUDIT_TRAIL parameter enables auditing to the table SYS$AUD$.
Auditing causes a record of database and user activity to be logged. Because
auditing causes overhead, it limits performance. The amount of overhead and the
effect on performance is determined by what and how much is audited. Once AUDIT_TRAIL
is enabled, auditing is turned on by the Oracle command AUDIT.
O7_DICTIONARY_ACCESSIBILITY [TRUE/FALSE] <TRUE>
If set to TRUE (default), access to the SYS schema is
allowed. This is Oracle7 behavior.
OS_AUTHENT_PREFIX [] <OPS$>
This is the value concatenated to the beginning of the user's OS login
account to give a default Oracle account name. The default value of OPS$
is OS dependent and is provided for backward compatibility with previous Oracle
versions. Typically, you use the default or set the value to ""
(NULL) to eliminate prefixes altogether.
OS_ROLES [TRUE/FALSE] <FALSE>
Setting this parameter to TRUE allows the OS to have control over
the username's roles. If set to FALSE, the username's roles are
controlled by the database.
SQL92_SECURITY [TRUE/FALSE] <FALSE>
This parameter specifies whether the table-level SELECT privileges
are needed to execute an update or delete that reference's table-column values.
TRANSACTION_AUDITING [TRUE/FALSE] <TRUE>
This parameter specifies that additional transaction information is included
in a special redo record.
The following parameters apply to the Trusted Oracle7 option.
AUTO_MOUNTING [TRUE/FALSE] <TRUE>
When set to TRUE, this parameter specifies that a secondary
database is mounted by the primary database whenever a user connected to the
primary database requests data from the secondary database.
DB_MOUNT_MODE [NORMAL/READ_COMPATIBLE] <NORMAL>
This parameter specifies the access mode to which the database is mounted at
instance startup. A value of NORMAL starts the database in normal
read-write mode; READ_COMPATIBLE starts the database in read-write mode
with the added feature of supporting concurrent mounting by one or more
read-secure instances.
LABEL_CACHE_SIZE [number> 50] <50>
This parameter specifies the cache size for dynamic comparison of labels.
This number should be greater than the label-category combinations in the OS and
should never be less than 50.
MLS_LABEL_FORMAT [valid label format] <sen>
This parameter specifies the format used to display labels. The default
value sen specifies sensitive.
OPEN_MOUNTS [0..255] <5>
This parameter specifies the maximum number of databases that an instance
can simultaneously mount in OS MAC mode. This value should be large enough to
handle all the primary and secondary databases you might mount.
The following parameters are used in the configuration of National Language Support features.
NLS_CURRENCY [character string] <derived from NLS_TERRITORY>
This parameter specifies the string to use as the local currency symbol for
the L number format element.
NLS_DATE_FORMAT [format mask] <derived from NLS_TERRITORY>
This parameter defines the default date format to use with the TO_CHAR
and TO_DATE functions. The value of this parameter is any valid date
format mask. Here is an example:
NLS_DATE_FORMAT = `DD/MM/YYYY'
NLS_DATE_LANGUAGE [NLS_LANGUAGE value] <value for NLS_LANGUAGE>
This parameter determines the language to use for the day and month names
and date abbreviations (AM, PM, AD, BC).
NLS_ISO_CURRENCY [valid NLS_TERRITORY value] <derived from
NLS_TERRITORY>
This parameter defines the string to use as the international currency
symbol for the C number format element.
NLS_LANGUAGE [NLS_LANGUAGE value] <OS dependent>
This parameter defines the default language of the database. This specifies
the language to use for messages, the language of day and month names, symbols
to be used for AD, BC, A.M. and P.M., and the default sorting mechanisms.
NLS_NUMERIC_CHARACTERS [two characters] <derived from NLS_TERRITORY>
This parameter defines the characters to be used as the group separator and
decimal. The group separator is used to separate the integer groups (that is,
hundreds, thousands, millions, and so on). The decimal separator is used to
distinguish between the integer and decimal portion of the number. Any two
characters can be used but they must be different. The parameter is specified by
two characters within single quotes. To set the group separator to ,
(comma) and the decimal separator to . (period), use the following
statement:
NLS_NUMERIC_CHARACTERS = `,.'
NLS_SORT [BINARY or named linguistic sort] <derived from
NLS_LANGUAGE>
If this parameter is set to BINARY, the collating sequence for ORDER_BY
is based on the numeric values of the characters. A linguistic sort decides the
order based on the defined linguistic sort. A binary sort is much more efficient
and uses much less overhead.
NLS_TERRITORY [territory name] <OS dependent>
This parameter specifies the name of the territory whose conventions are
used for day and week numbering. The parameter also provides defaults for other
NLS parameters.