default: 0
change: DIRECT
new in 7.9.10.05
This parameter is a DBM Server configuration parameter. If "AutoTruncateBackupHistory" is set to a value of 182 <= "AutoTruncateBackupHistory" < 3650 the backup history files are truncated at each complete data backup so that at least a period of the given value (days) remains in the backup history files. The truncation takes place as defined by the DBM Server command "db_truncatehistory DATE (- 'AutoTruncatebackupHistory')". A value of '0' means no automatic truncation is active. The default value is 0 days, i.e. the feature is deactivated.
change: RUNNING
new in 7.9.09.01
CatalogCacheSupply is the reserved space for all task-specific catalog caches. For each user task a minimum part of the catalog cache is reserved. (TaskSpecificCatalogCacheMinSize) Each task may extend its catalog cache unless all task-specific catalog caches together do not exceed the catalog cache supply. The catalog cache supply influences the performance. The best performance can be achieved at a catalog cache hit rate of 100%. Use the database monitoring to get information about the catalog cache hit rate. The lower and upper limits are: (MaxUserTasks + PreservedDBAnalyzerTasks + MaxServerTasks + MaxUtilityTasks) * 2 * TaskSpecificCatalogCacheMinSize <= CatalogCacheSupply and 30000 <= CatalogCacheSupply <= 2147483647 Default calculation, can be overridden CatalogCacheSupply := (MaxUserTasks + PreservedDBAnalyzerTasks + MaxServerTasks + MaxUtilityTasks) * 2 * TaskSpecificCatalogCacheMinSize but at least 30000 TaskSpecificCatalogCacheMinSize depends on CommandBufferSize (4 bytes integer)
default: depends on operating system or instance type
change: RUNNING
defines the degree of heap checking
0 disables heap checking
The value is a bit field and can be set as follows:
CheckAllocator & 1 - places a pattern after each used chunk. It will be checked when the chunk is freed
CheckAllocator & 2 - fill the chunks with a pattern when it is freed
CheckAllocator & 4 - double bookkeeping of used chunks
CheckAllocator & 8 - check binary tree of big free chunks
CheckAllocator & 16 - check exclusive usage of unsynchronized heaps
CheckAllocator & 32 - delay the reuse of freed chunks (delayed free)
CheckAllocator & 64 - check in use chunks (kernel only)
CheckAllocator & 128 - check in use OMS chunks
(4 bytes integer)
default: 10
change: RUNNING
The lower and upper limits are: 0% <= ClusterCompressionFillThreshold <= 50% Clusters with up to ClusterCompressionFillThreshold occupied blocks will be considered for compression. Percent value of the DataIOClusterSize 0 will disable compression
default: 80
change: RUNNING
The lower and upper limits are 0% and 100% Minimum number of blocks to write into a cluster. Percent value of the DataIOClusterSize
change: OFFLINE
Optional comment for the database (64 byte character)
default: 8
change: OFFLINE
Number of autonomous units of the component converter in which parallel working is done. Note that the number of ConverterStripes are determined by a calculation regulation which depends on the capacity of the DATA_AREA (parameter DataVolumeSize*). The lower and upper limits are: 1 <= ConverterStripes <= 64 DATA_AREA_SIZE <= 62 GB --> ConverterStripes = 8 62 GB < DATA_AREA_SIZE <= 125 GB --> ConverterStripes = 16 125 GB < DATA_AREA_SIZE <= 250 GB --> ConverterStripes = 32 250 GB < DATA_AREA_SIZE <= 500 GB --> ConverterStripes = 48 500 GB < DATA_AREA_SIZE --> ConverterStripes = 64 (2 bytes integer)
default: 8
change: OFFLINE
Number of bits in a four byte converter block address reserved for the logical devive number which identifies the data volumes. The rest of the four byte block address is used for the device offset. The greater the ConverterVolumeIdLayout the more data volume could be managed. Note that this reduces the capacity of usable data volumes! This value is not changeable within the lifetime of the data base without making a recovery. Example: If ConverterVolumeIdLayout is set to the default value of 8 then the data base is able to manage as far as 256 data volumes, whereby the maximum capacity of one data volume is 128 GB. If the ConverterVolumeIdLayout is set to 6 the data base is able to manage up to 64 data volumes, whereby the capacity of one data volume is 512 GB. The lower and upper limits are: 6 <= ConverterVolumeIdLayout <= 12
change: OFFLINE
Number of autonomous units of the data cache in which parallel working is done. Note that the number of DataCacheStripes are determined by a calculation regulation which depends on the capacity of the parameter CacheMemorySize. The lower and upper limits are: 1 <= DataCacheStripes <= 1024 CacheMemorySize <= 10000 --> DataCacheStripes = 8 10000 < CacheMemorySize <= 50000 --> DataCacheStripes = 16 50000 < CacheMemorySize <= 100000 --> DataCacheStripes = 32 100000 < CacheMemorySize <= 150000 --> DataCacheStripes = 48 150000 < CacheMemorySize <= 1000000 --> DataCacheStripes = 64 1000000 < CacheMemorySize <= 4000000 --> DataCacheStripes = 128 4000000 < CacheMemorySize <= 8000000 --> DataCacheStripes = 256 8000000 < CacheMemorySize <= 12000000 --> DataCacheStripes = 512 12000000 < CacheMemorySize --> DataCacheStripes = 1024 (2 bytes integer)
default: "INTERNAL"
possible values: "INTERNAL" "ISO" "EUR" "JIS" "USA"
change: RUNNING
Alterable default format of date, time and timestamp values for non-JDBC and non-ODBC applications date format time format timestamp format __________________________________________________ 'INTERNAL' YYYYMMDD HHHHMMSS YYYYMMDDHHMMSSMMMMMM 'ISO' YYYY-MM-DD HH:MM:SS YYYY-MM-DD HH:MM:SS.MMMMMM 'EUR' DD.MM.YYYY HH.MM.SS YYYY-MM-DD-HH.MM.SS.MMMMMM 'JIS' YYYY-MM-DD HH:MM:SS YYYY-MM-DD-HH.MM.SS.MMMMMM 'USA' MM/DD/YYYY HH:MM AM YYYY-MM-DD-HH.MM.SS.MMMMMM
default: 4
change: RUNNING
Maximum search level for deadlock detection.
The lower and upper limits are:
0 <= DeadlockDetectionLevel <= 10000
0 : deadlock detection is disabled, deadlocks are only
cancelled by the RequestTimeout.
> 0 : deadlocks not detected by the deadlock detection within the given
search level are only cancelled by the RequestTimeout.
(4 bytes integer)
default: "ASCII"
possible values: "ASCII" "UNICODE"
change: RUNNING
Default code taken as code attribute for CHAR columns defined without code attribute, for open systems usually ASCII code DEFAULT CODE = 'ASCII' or 'UNICODE' (UNICODE is only valid for a unicode database) (char(18))
default: "EXECUTE"
possible values: "EXECUTE" "PREPARE"
change: RUNNING
DeterministicFunctionExecution 'EXECUTE' or 'PREPARE'
'EXECUTE': Deterministic result of user defined functions will be calculated at execution time
'PREPARE' : Deterministic result of user defined functions will be calculated at prepare time
default: 2
change: OFFLINE
Number of diagnostic file histories written after an abnormal database shutdown Number of histories in the DiagnoseHistoryPath. At database start some important diagnostic files are saved to a history directory named '_ ' which is created under the DiagnoseHistoryPath located in the RunDirectoryPath. If the number of histories is reached the oldest history is deleted and the new one is written instead. The value has to be greater than 0 to insure that at least one backup of diagnostic files can be initiated after an abnormal database shutdown. The default number of histories is 2. (4 bytes integer)
change: OFFLINE
This directory holds different kinds of diagnostic histories which are located under further subdirectories. First of all the histories of diagnostic files after a abnormal database shutdown are located in this directory. Furthermore a history of the last kernel message files is also located in this directory. The default directory for this is "DIAGHISTORY" which is created under the specified RunDirectoryPath. (256 bytes character)
default: "YES"
possible values: "YES" "NO"
change: RUNNING
EnableIndexOnlyStrategy 'YES' or 'NO'
'YES': avoid base table access with a primary key fetched from an index
( if possible )
'NO' : access base table with primary key fetched from an index
(char(8))
default: "NO"
possible values: "YES" "NO"
change: OFFLINE
EnableLogBackupToPipe = 'YES' or 'NO'
Allow the usage of pipes for log backup similar to files.
This includes the automatic release of log after the backup
although the database can not check if the backup was successful.
For the usage of pipes with 3rd party backup tools set this
parameter to NO. With 3rd party backup tools the log will be
released automatically after the database checked the success
of the backup.
Possible values are:
'YES' : log will be freed automatically without check of the backup into the pipe
'NO' : log will be not freed automatically (except for 3rd party backup tools)
(8 byte character)
default: "YES"
possible values: "NO" "YES"
change: RUNNING
EnableQueryRewrite 'NO' or 'Yes'
'NO' : No query rewrite will be done.
'YES' : Query will be rewritten if possible.
default: 2
change: RUNNING
The tasks will skip the active waiting phase during
the exclusive-lock collision if the waiting queue
filling exceeds this threshold.
The limits are:
2 <= ExclusiveLockEnqueueThreshold
(4 bytes integer)
default: "DEFAULT"
possible values: "YES" "NO" "DEFAULT"
change: RUNNING
This parameter specifies whether or not a priority task that does
not obtain a critical region at once is to be favored when another
task frees this region.
ExclusiveLockFavorPrioTasks = 'YES', 'NO' or 'DEFAULT'
'YES' means: If a priority task tries to obtain a region used by
another task (collision), the priority task will add
itself to a special queue in order to obtain the region
as soon as the other task frees the region.
'NO' means: see parameter MaxExclusiveLockCollisionLoops
'DEFAULT' means:
IF MaxCPUs > 1
THEN
act as if set to 'YES'
ELSE
act as if set to 'NO'
(char(8))
default: -1
change: RUNNING
Maximum number of attempts a task can make to obtain a region
without being interrupted by another task in this UKT.
When this number is reached without success, the task
interrupts itself and falls asleep.
If this parameter is set to -1, a default value is chosen by
the kernel. The default value is 300 for MaxCPUs = 1 and 3000
for MaxCPUs > 1.
If LockRescheduleInterval has been set (value not equal to 0),
the lower and upper limits are:
0 <= ExclusiveLockRescheduleThreshold <= 10000
Otherwise:
100 <= ExclusiveLockRescheduleThreshold <= 10000
(4 bytes integer)
default: 10
change: OFFLINE
This parameter controls the number of spinlocks available for the file directory spinlock pool. The file directory uses a large number of reader/writer locks to provide maximum concurrency during operation. When changing states of any of those reader/writer locks a spinlock has to be used to protect that lock's internal state change. Since spinlocks are expensive in terms of memory and cache usage every reader/writer lock is mapped to one specific spinlock from a spinlock pool. This means that several reader/writer locks share the same spinlock to protect their internal state. If you have many tables/objects and a high degree of concurrency in your database the default setting of FileDirectorySpinlockPoolSize might lead to a bottleneck because reader/writer lock accesses have to serialize on the available spinlocks. You can determine if this is the case by checking the values for column COLLISIONCOUNT in rows with name 'FileDir%' in the system view SPINLOCKSTATISTICS. If these seem unusually high for most of the available spinlocks you should increase FileDirectorySpinlockPoolSize. Configuring too high a FileDirectorySpinlockPoolSize will not improve the database performance but only waste precious resources.
default: "YES"
possible values: "YES" "NO"
change: OFFLINE
FormatDataVolume = 'YES' or 'NO'
In order to speed up the installation process
on personal development systems the formatting
of data volumes (type file) can be suppressed.
It is not recommended to suppress the formatting
of data volumes on productive systems. The formatting process
occupies the desired space on disk. Therefor omitting it
may lead to a system crash during runtime if the system
is low on disk space.
Possible values are:
'YES' : Formatting of data volumes is performed (default)
'NO' : Formatting of data volumes is suppressed
default: 65536
change: RUNNING
The maximum cache size in KB used for each hashed resultset
The lower and upper limits are:
32768 (=32MByte) <= HashedResultsetCacheSize <= 8388608 (=8GByte)
default: 4000
change: RUNNING
The maximum table size in KB for which hash joins will be executed.
The lower and upper limits are:
0 <= HashJoinSingleTableMemorySize <= HashJoinTotalMemorySize
If HashJoinSingleTableMemorySize = 0 then no hash tables will be created during
join execution.
default: 24000
change: RUNNING
The maximum memory in KB that can be used for hash joins at any time. As there can be multiple hash joins running at the same time, the amount of memory used for all hashes might become excessive if it is unlimited. This parameter sets the upper limit for the memory provided for all hash joins that are running in parallel. If during join execution a join transition qualifies for a hash join but the overall memory used for all hash joins would be more than HashJoinTotalMemorySize a regular join will be executed instead. If HashJoinTotalMemorySize = 0 then no hash joins will be executed.
default: depends on operating system or instance type
possible values: "CPU" "GETTIMEOFDAY" "PERFCNTR" "TICKS" (values depend on operating system)
change: OFFLINE
Specifies the high resolution timer type used by the database kernel.
Possible values are:
CPU:
Direct access to the CPUs hight resolution counters.
GETTTIMEOFDAY:
Using system gettimeofday() system call.
PERFCNTR:
Using 'QueryPerformanceCounter' functionality.
TICKS:
Using system clock ticks.
In some very rare situations the result that is returned by the CPU counters may
unexpectedly leap forward from time to time. This leap may represent several seconds
due to some hardware design defects or different CPU speeds in multi CPU environments.
This parameter allows to overrule the default usage of CPU timers which is faster.
(char(16))
change: OFFLINE
Specifies the database name in a high availability system using no shared resources used to connect between master and standby server. A three digit number is used to specify the names leading to a range from HotStandbyDatabaseName001 up to HotStandbyDatabaseName999. The default for additional databases in a high availability system will be the name of the master database. This parameter does not apply to high availability systems using a shared log area! (char(64))
change: OFFLINE
In a high availability configuration using a shared log area, this parameter specifies the local node delay time in seconds. A three digit number is used to specify the specific nodes leading to a range from HotStandbyDelayTime001 up to HotStandbyDelayTime999 This parameter does not apply to high availability systems using no shared resources! (char(64))
change: OFFLINE
Specifies the local node name of a high availability node used to connect between master and standby server. A three digit number is used to specify the nodes leading to a range from HotStandbyNodeName001 up to HotStandbyNodeName999. HotStandbyNodeName001 has the special role of being default master node. (char(64))
change: OFFLINE
Only needed for a high availability configuration, that means if at least HotStandbyNodeName001 is configured too.
When high availability using a shared log area is configured, the storage access is encapsulated in a
separated dynamic link library (DLL).
This parameter allows to setup the name of that DLL. Different DLLs for different storage
system are possible. The DLL is itself loaded dynamically on demand in high availability code sections.
Example HotStandbyStorageDLLPath names are "libhsscopy" and "libhssemc".
For a high availability system without shared log area, no DLL is used. To indicate such a system, leave
the value of this parameter blank (default).
(256 bytes character)
default: 50
change: OFFLINE
Specifies the time interval in seconds between two synchronize commands of the master node in a high availability configuration. In a high availability configuration using a shared log area the master node sends synchronize commands to the standby nodes. The minimum time interval between two successive synchronize commands is defined by the parameter HotStandbySyncInterval. The synchronize command is initiated by the timeout task. This leads to an inaccuracy of this parameter because it is only tested once during the runtime of the timeout task. The lower and upper limits are: 0 <= HotStandbySyncInterval <= 36000 This parameter does not apply to high availability systems using no shared resources! (4 bytes integer)
default: 500
change: RUNNING
Strategies for merging index lists produce a temporary index which implies space and time consumption. To minimize these disadvantages those strategies are only used when the number of index pages involved is less than or equal to IndexlistsMergeThreshold. As an alternative the strategy which only works on the base table is used. The lower and upper limits are: 0 <= IndexlistsMergeThreshold (4 bytes integer)
default: 0
change: RUNNING
The lower and upper limits are:
0 <= JoinSearchLevel <= 9
A search level determines time and effort of join sequence search.
With level 9 most of all possible join sequences will be evaluated.
A simple algorithm will be used with level 1. Level 0 means graded search
level according to participated tables. Up to JoinSearchTableThreshold9 tables
level 9 will be used, up to JoinSearchTableThreshold4 tables level 4 will
be used.
(4 bytes integer)
default: 16
change: RUNNING
The lower and upper limits are: 2 <= JoinSearchTableThreshold4 <= 64 Level 4 sequence search for joins with up to JoinSearchTableThreshold4 tables. This threshold will be used with automatic join search level ( JoinSearchLevel = 0 ) (4 bytes integer)
default: 8
change: RUNNING
The lower and upper limits are: 2 <= JoinSearchTableThreshold9 <= 64 Level 9 sequence search for joins with up to JoinSearchTableThreshold9 tables. This threshold will be used with automatic join search level ( JoinSearchLevel = 0 ) (4 bytes integer)
default: 256
change: RUNNING
Specifies the minimal amount of buffer size (in KB) per user task for table buffers used during join execution (4 bytes integer)
default: 10000
change: OFFLINE
Size of the file which contains all messages, warnings, and errors
of the database kernel.
The file is written cyclically.
The lower limit is:
800 <= KernelMessageFileSize
(2 bytes integer)
default: 20
change: OFFLINE
Number of kernel message file backups. At database start the last kernel message file 'KnlMsg' is moved to a history directory named 'History_KnlMsg' which is created under the DiagnoseHistoryPath located in the RunDirectoryPath. A timestamp is added to the name of the kernel message file when it is moved to the history. If the number of message files in the history is reached the oldest message file is deleted and the new one is written instead. The value has to be greater than 0 to insure that at least one backup of the kernel message file can be written. The default number of files in the history is 20. (4 bytes integer)
default: 1
change: RUNNING
Load balancing means distributing tasks across multiple
threads (UKTs) within the database kernel.
The parameter LoadBalancingCheckInterval determines the
the time how often a check will be made
to find a task which have to move to another thread (UKT).
Possible values are:
0:
No load balancing will be made.
between 1 and 600:
Time in seconds, how often a balancing check is made.
(integer)
default: 0
change: OFFLINE
If this is set to a value greater than 0, a local buffer for each transaction is allocated. The given value is the buffer size in Bytes. The buffer is used to store redo entries before flushing them at once to the log volume. If the number of log queues (see parameter LogQueues) is greater than 1, no local redo buffer can be used.
default: 0
change: RUNNING
The parameter LogQueues defines the number of log queues, which are used for writing onto the log volume. If set to 0 the value will be set to the value of parameter MaxLogQueues. The lower and upper limits are: 0 <= LogQueues <= MaxLogQueues (2 bytes integer) More than 1 LogQueue is only possible if parameter LocalRedoLogBufferSize is set to 0. Otherwise LogQueue is set to 1.
default: depends on operating system or instance type
change: OFFLINE
The LogQueueSize defines the size of a single log queue (see parameter LogQueues for the number of log queues) in pages. By adjusting the LogQueueSize peak loads can be avoided and a larger LogIOClusterSize can be used when writing to the log. Use the database monitoring to get information about the number of LOG QUEUE OVERFLOWS and LOG QUEUE MAX USED ENTRIES. The lower and upper limits are: LogQueueSize < LogVolumeSize* AND LogQueueSize * MaxLogQueues < LogVolumeSize* AND LogQueueSize >= 2 * LogIOClusterSize (2 bytes integer)
default: 150
change: OFFLINE
Maximum number of events cached by the kernel for being processed by the Database Manager. The lower limit of 0 disables the caching of any event. It is not recommended to disable the caching of events, if not for minimizing memory consumption since the database manager can only process cached events. If no events are cache the database manager cannot report any events. (2 bytes integer)
default: -1
change: RUNNING
Maximum number of attempts made to obtain a region used by another
task (collision).
If the attempt fails, the UKT falls asleep (semop).
Set this parameter > 0 ONLY in combination with UseableCPUs > 1.
If this parameter is set to -1, a value is chosen by the kernel
as follows:
IF MaxCPUs = 1
THEN
MaxExclusiveLockCollisionLoops := 0
ELSIF MaxCPUs < 8
MaxExclusiveLockCollisionLoops := 1000
ELSE
MaxExclusiveLockCollisionLoops := 100000
(4 bytes integer)
default: 10000
change: RUNNING
If this parameter is set to a value other than 0, it defines a maximum size (in KB) for the file KnlMsgArchive (containing archived messages of the database kernel). If this size (in KB) is reached, the file is closed and renamed to KnlMsgArchive_. A new file KnlMsgArchive is then created for any coming error messages generated. (2 bytes integer)
default: 0
change: OFFLINE
Used for defining the number of log writer tasks for multiple log partitions
default: depends on operating system or instance type
change: OFFLINE
Maximum number of trace files which can be opened in parallel (liveCache Instances only)
The limits are:
64 <= MaxParallelLiveCacheTraceFiles <= 120
(2 bytes integer)
default: 200
change: RUNNING
The maximum length of a string passed as unspecific parameter argument to functions. These parameter arguments are used mostly in LPAD, RPAD, COALESCE system functions.
default: 480
change: RUNNING
Forces the garbage collector to remove consistent views which are older than MaxRetentionTime. Time is specified in minutes. The lower and upper limits are: MinRetentionTime <= MaxRetentionTime If MaxRetentionTime = 0 then no consistent view is cancelled by the garbage collector because of being too old. If MinRetentionTime = 0 AND MaxRetentionTime = 0 no consistent views will ever be cancelled by garbage collection. (4 bytes integer)
default: 0
change: OFFLINE
Server tasks are used for restart, backup/restore, savepoint, create index and update statistics operations and savepoints.
Overconfiguration exceeding the actual requirement results in an excessive
demand for address space.
MaxServerTasks >= ReservedServerTasks +
MinCheckDataParallelServerTasks +
1 ( = used for ASYNC DROP )
(2 bytes integer)
default: 1
change: OFFLINE
new in 7.9.10.00
Maximum number of simultaneously active utility tasks. The utility task(s) can be used in cases where all user tasks are blocked to solve database- or log-full situations. (2 bytes integer)
default: "HighResolutionTimer"
possible values: "HighResolutionTimer" "SystemTimer"
change: OFFLINE
Specifies the timer type used for time stamps etc.
Possible values are:
HighResolutionTimer:
Using the fast high-resolution-timer
SystemTimer:
Using the standard operating system timer.
(char(40))
default: 60
change: RUNNING
Forbids the garbage collector to remove consistent views which are younger than MinRetentionTime. Time is specified in minutes. The lower and upper limits are: 0 or 3 < MinRetentionTime <= 1440 (one day) If MinRetentionTime = 0 then no consistent view is cancelled by the garbage collector because of MinRetentionTime even with resource shortage. If MinRetentionTime = 0 AND MaxRetentionTime = 0 no consistent views will ever be cancelled by garbage collection. (4 bytes integer)
change: RUNNING
OfficialNodeName
The official node name of the host of the database
kernel may be ambiguous or even misleading.
Especially in a cluster configuration with several network
interfaces the decision which name is to be used by clients
to establish a remote connection is problematic. Each
interfaces must defines its own 'hostname'.
If this parameter is set, the database kernel always
uses it instead of the default value.
If it is not set (which is default) the database
kernel uses the nodename retrieved by
'uname()' call (UNIX)
Since some administrators misuse 'uname' for a nickname
of their computer, it is a way to keep the nickname
and still allow clients to connect...
or
official hostname (NT).
The official hostname is retrieved by first
using GetComputerName()
followed by get_host_by_name()
and finally get_host_by_addr().
This results normally in the first name given
in the alias list in /etc/hosts where the
computer name is found or in the computer name
retrieved by the 'hostname' command if /etc/hosts
does not have a corresponding entry.
(char(64))
default: 10000
change: OFFLINE
each time the OMS Heap is growing, a memory block of OmsHeapBlockSize KB is required from the operating system The lower and upper limits are: 10 <= OmsHeapBlockSize <= 524000 (4 bytes integer)
default: 100
change: OFFLINE
defines the heap usage (in percent) when the livecache starts to reduce the heap usage of OMS versions, i.e. at transaction end all unchanged objects are removed from the version context. (4 bytes integer)
default: 1
change: OFFLINE
defines the number of sub heaps of the OMS heap. In case of a single
OMS heap becomes a bottleneck in multi CPU environments, multiple sup heaps
may increase speed and scalability.
The lower limit is:
OmsSubHeaps >= 1
The upper limits are:
OmsSubHeaps <= 128 and
OmsSubHeaps <= MaxCPUs
(4 bytes integer)
default: 2097152
change: OFFLINE
defines the size of a OMS version (in KB) when the liveCache starts to reduce the heap usage of that versions, i.e. at transaction end all unchanged objects are removed from the version context. (4 bytes integer)
default: "YES"
possible values: "YES" "NO"
change: RUNNING
OracleConcatNULLYieldsNULL 'YES' or 'NO'
'YES': Concatenating a NULL value with a string yields a NULL result
'NO' : Concatenating a NULL value with a string yields a string result
default: "NO"
possible values: "YES" "NO"
change: OFFLINE
new in 7.9.10.03
This parameter specifies whether liveCache object containers are prefetched during redo (including standby databases).
PreloadObjectsDuringRedo = 'YES' or 'NO'
'YES': object containers are prefetched
'NO' : object containers are not prefetched
default: 3600
change: RUNNING
Restricts for all database sessions the waiting time for a lock to be released by other users.
The time is specified in seconds.
If a lock request cannot be satisfied within the time defined,
a message is returned to the waiting database session.
The lower and upper limits are:
5 <= RequestTimeout <= 100000
(4 bytes integer)
default: 30
change: RUNNING
If the optimizer detects that a table's size has changed by more
than RequestUpdateStatisticsThreshold percent since the latest
collection of statistics information, it will request the
statistics information for this table to be updated by inserting
a row with this table's name into the system table SYSUPDSTATWANTED.
default: 8
change: OFFLINE
Number of autonomous units in which lock collisions in rows are checked in parallel
The lower and upper limits are:
1 <= RowLockManagementStripes <= 64
(2 bytes integer)
default: 50
change: RUNNING
If a transaction holds as many row locks as defined by this parameter, all further attempt to get a lock results in an escalation attempt. The allowed range is 0 to 100 % and the default is 50 % of MaxSQLLocks. If 0 % is set this additional escalation behaviour is disabled.
default: 20
change: RUNNING
new in 7.9.10.00
If a table holds as many row locks as defined by this parameter, all further attempt to get a lock results in an escalation attempt. The allowed range is 1 to 100 % and the default is 20 % of MaxSQLLocks. 0 disables lock escalation due to table locks at all.
default: 10
change: OFFLINE
The value depends on the number of sequences used simultaneously.
Use the database monitoring to obtain information about the
sequence cache hit rate
The lower and upper limits are:
1 <= SequenceCacheSize <= 2147483640
(4 bytes integer)
default: 900
change: RUNNING
Maximum time of inactivity allowed for all database sessions.
The time is specified in seconds.
If no SQL statement is issued within the specified time, the database
session concerned is terminated (ROLLBACK WORK RELEASE).
The lower and upper limits are:
30 < SessionTimeout <= 32400
SessionTimeout = 0 : no timeout of session
(4 bytes integer)
default: 75
change: RUNNING
Defines the threshold (%) from which on clean up occurs within SharedSQL
default: 262144
change: RUNNING
Specifies the maximum size (in KB) for SharedSQL statement caching (4 bytes integer).
The lower and upper limits:
32768 (=32MByte) <= UseSharedSQL_COMMANDCACHESIZE < 8388608 (=8GByte)
In any case the initial size will be 16MByte, the supplemental size 2MByte.
default: 8
change: OFFLINE
TableLockManagementStripes help to improve simultaneity when checking lock collisions on tables. The value of TableLockManagementStripes should be increased when the number of tables increases. The lower and upper limits are: 1 <= TableLockManagementStripes <= 64 (2 bytes integer)
default: 300
change: OFFLINE
new in 7.9.10.00
Maximum time the TaskScheduler is allowed to spend in the startup-phase
The time is specified in seconds.
The lower and upper limits are:
30 < TaskSchedulerStartupTimeout <= 32400
(4 bytes integer)
default: 5
change: OFFLINE
new in 7.9.09.01
Size (in pages) of the memory used for kernel trace of task(s) of type ALR (automatic-log-backup-reader)
The file is written cyclically.
The lower limit is:
0 <= TraceBufferSizeALRTask
(2 bytes integer)
default: 5
change: OFFLINE
new in 7.9.09.01
Size (in pages) of the memory used for kernel trace of task(s) of type ALW (automatic-log-backup-writer)
The file is written cyclically.
The lower limit is:
0 <= TraceBufferSizeALWTask
(2 bytes integer)
default: 5
change: OFFLINE
Size (in pages) of the memory used for kernel trace of task(s) of type EV (event) / AN (dbanalyzer)
The file is written cyclically.
The lower limit is:
0 <= TraceBufferSizeFSTask
(2 bytes integer)
default: 20
change: OFFLINE
Size (in pages) of the memory used for kernel trace of task(s) of type GC (garbage collector)
The file is written cyclically.
The lower limit is:
0 <= TraceBufferSizeGCTask
(2 bytes integer)
default: 5
change: OFFLINE
new in 7.9.09.01
Size (in pages) of the memory used for kernel trace of task(s) of type IOC (I/O-completion)
The file is written cyclically.
The lower limit is:
0 <= TraceBufferSizeIOCTask
(2 bytes integer)
default: 5
change: OFFLINE
Size (in pages) of the memory used for kernel trace of task(s) of type AL (archive log)
The file is written cyclically.
The lower limit is:
0 <= TraceBufferSizeLWTask
(2 bytes integer)
default: 5
change: OFFLINE
new in 7.9.09.01
Size (in pages) of the memory used for kernel trace of task(s) of type RR (redo-reader)
The file is written cyclically.
The lower limit is:
0 <= TraceBufferSizeRRTask
(2 bytes integer)
default: 5
change: OFFLINE
new in 7.9.09.01
Size (in pages) of the memory used for kernel trace of task(s) of type SVP (savepoint)
The file is written cyclically.
The lower limit is:
0 <= TraceBufferSizeSVPTask
(2 bytes integer)
default: 5
change: OFFLINE
Size (in pages) of the memory used for kernel trace of task(s) of type SV (server)
The file is written cyclically.
The lower limit is:
0 <= TraceBufferSizeSVTask
(2 bytes integer)
default: 2
change: OFFLINE
Size (in pages) of the memory used for kernel trace of task(s) of type TI (timeout)
The file is written cyclically.
The lower limit is:
0 <= TraceBufferSizeTITask
(2 bytes integer)
default: 10
change: OFFLINE
Size (in pages) of the memory used for kernel trace of task(s) of type US (user)
The file is written cyclically.
The lower limit is:
0 <= TraceBufferSizeUSTask
(2 bytes integer)
default: 5
change: OFFLINE
Size (in pages) of the memory used for kernel trace of task(s) of type UT (utility)
The file is written cyclically.
The lower limit is:
0 <= TraceBufferSizeUTTask
(2 bytes integer)
default: 0
change: OFFLINE
Information for long running transactions is kept within a wrap around buffer in memory. TransactionHistorySize defines the maximum number of entries hold within this buffer. If TransactionHistorySize = 0 then no information for long running transaction will be kept.
default: 60
change: RUNNING
If a transaction lived longer than TransactionHistoryThreshold seconds, then its
will be inserted into the history buffer for long running transactions.
default: 8
change: OFFLINE
The specified number of regions allows for simultaneous transaction management. The value of TransactionLockManagementStripes should be increased when the number of parallel working sessions increases. The lower and upper limits are: 8 <= TransactionLockManagementStripes <= 1024 Note: values < 8 can be set in restart error situation When the database is online switch the value back to >= 8 Default calculation, can be overridden MaxCPUs = 1 ---> TransactionLockManagementStripes = 8 (2 bytes integer)
default: 1
change: RUNNING
Selects the algorithm used for sampling during processing of 'Update
Statistics ... Estimate ...' statements.
0: Use the classic algorithm (should not be used anymore)
1: Use an improved algorithm (Default setting)
2: Use another improved algorithm that might have a greater tendency to
overestimate the distinct value count.
3: Use the classic algorithm with a different sampling algorithm.
4: Use a combination of 1 and 2.
default: 0
change: RUNNING
new in 7.9.09.05
Defines the number of temporary files used by 'Update Statistics' to count distinct values.
Increase UpdateStatTempFiles, if you observe huge numbers of collisions on
temporay files used by 'Update Statistics'.
If this parameter is set to 0, a value is chosen by the kernel.
default: "YES"
possible values: "YES" "NO"
change: RUNNING
If set to 'YES' default values of added columns are not materialized immediately. This saves execution time in case of large tables. If set to 'NO' all table rows are updated with the default values of the added columns.
default: "NO"
possible values: "YES" "NO"
change: RUNNING
Specification of scan performance in the data cache
'YES' : The complete data cache will be used for scans.
This setting is advantageous if small tables are to
be kept completely in the data cache.
'NO' : Only part of the data cache will be used for scans.
(char(8))
default: "YES"
possible values: "YES" "NO"
change: RUNNING
UseHashedResultset 'YES' or 'NO'
'YES': Hashed resultsets are used for aggregates
'NO' : Hashed resultsets will not be used
default: "NO"
possible values: "YES" "NO"
change: RUNNING
If set to 'YES' keys stored in indexes are stored in a compressed format. This saves disk space and allows more index data inside the data cache. On the other hand decompression needs some additional CPU power.
default: "YES"
possible values: "YES" "NO"
change: RUNNING
'YES': Enable clustered storage of LOB file
default: "YES"
possible values: "YES" "NO"
change: RUNNING
UseParameterInfoForColumn 'YES' or 'NO'
'YES': Application info description will be evaluated for native Column Parameter
'NO' : Application info description will not be evaluated for native Column Parameter
default: "YES"
possible values: "NO" "YES"
change: RUNNING
UseQueryRewriteInDBProcedures 'NO' or 'Yes'
'NO' : Query rewrite won't be used at compile time of database procedures
'YES' : Query rewrite will be used at compile time of database procedures
default: "YES"
possible values: "YES" "NO"
change: RUNNING
UseSharedSQL 'YES' or 'NO'
'YES': SharedSQL is used for caching SQLCommands
'NO' : SharedSQL will not be used
default: "NO"
possible values: "YES" "NO"
change: RUNNING
If set to 'YES' non-key columns of type '(VAR)CHAR UNICODE' and variable width will not be stored in UCS2 but in UTF8 format on disk for newly created tables. This will result in disk space savings at the cost of increased CPU consumption. Tables for which this optimization is enabled will show the value 'YES' for column 'PACKEDUNICODECOLUMNS' in the system table 'FILES'. Changing this parameter will not affect existing tables.
default: "PARALLEL"
possible values: "PARALLEL" "SERIAL" "AUTO" (values depend on operating system)
change: OFFLINE
&if $OS in [ WIN32 ] VolumeFormattingMode 'PARALLEL' or 'SERIAL' 'PARALLEL': Volumes are being formatted in parallel 'SERIAL': Volumes are being formatted in serial &else VolumeFormattingMode 'PARALLEL', 'SERIAL, or 'AUTO' 'PARALLEL': Volumes will be formatted in parallel 'SERIAL': Volumes will be formatted serially one after another 'AUTO' : The database system forms groups of volumes which reside on the same device. Those groups will be formatted in parallel, but the members of the groups itself will be formatted serially. &endif It is recommended that each volume is located on its own device. This way the maximum I/O performance for the database system is guarantied and parallel formatting achieves the best performance. Notice that this parameter setting only affects the format process during initialization of the database (not used during ADD volume). The default setting is 'PARALLEL'. (char(8))