ttDBConfig
The ttDBConfig built-in enables users to set or view the value of a TimesTen database system parameter.
Required Privilege
This procedure requires ADMIN privilege.
Usage in TimesTen Scaleout and TimesTen Classic
This procedure is supported in TimesTen Classic.
This procedure is supported in TimesTen Scaleout, but it runs locally on the element from which it is called.
Syntax
ttDBConfig(['param'[,'value']])
Parameters
ttDBConfig has the parameters:
| Parameter | Type | Description |
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A system parameter for which you either want to set a value or see the current value. Accepted values for this argument are:
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The value of the system parameter. If you do not specify a value, this procedure returns the current value of the specified parameter. |
Parameter / Value Pairs
These name/value pairs can be returned in the result set:
| Name | Value | Description |
|---|---|---|
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Size in MB |
Specifies the reclaim buffer maximum size for the cache agent. The cache agent periodically checks to see if the value has changed. The size cannot be greater than the temporary partition size. For more details, see Improving Performance When Reclaiming Memory During Autorefresh Operations in Oracle TimesTen In-Memory Database Cache Guide. |
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Determines whether PL/SQL or SQL array method is used for AWT propagation to apply changes to the Oracle database server. Setting this parameter withttDBConfig overrides the connection attribute value.
Default: CacheAWTMethod connection attribute for details.
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Number of rows in a batch |
Configures a threshold value for the number of rows included in a single batch. Once the maximum number of rows is reached, TimesTen includes the rest of the rows in the transaction (TimesTen does not break up any transactions), but does not add any more transactions to the batch. Note: You should not change the value of this parameter unless advised by Oracle TimesTen technical support. |
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If enabled, changes the way that autorefresh and dynamic load operations coordinate, which results in reduced contention between autorefresh and dynamic load operations.
Default: For more details, see Reducing Contention on TimesTen for Dynamic Read-Only Cache Groups with IncrementalAautorefresh in Oracle TimesTen In-Memory Database Cache Guide. |
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Number of seconds |
Specifies the number of seconds of drift to allow between the parallel replication tracks. When you use automatic parallel replication with disabled commit dependencies, some of the tracks may move ahead of the others. Once this threshold is passed, TimesTen synchronizes all replication tracks so that they catch up to each other. By default, this is set to zero, which means that checking for drift between tracks is disabled. |
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Maximum number of PL/SQL cursors |
Specifies the maximum number of PL/SQL cursors that can be open in a session at one time, a value from 1 to 65535, inclusive. Use this to prevent a session from opening an excessive number of cursors. Setting this parameter with Default: 50 PL/SQL cursors. For more details see the description of the PLSQL_OPEN_CURSORS connection attribute. |
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Number of session cursors to cache |
Specifies the number of session cursors to cache. A user may adjust the setting to free up space not currently needed in the cache.
Default: 50 PL/SQL cursors. For more details, see the description of the PLSQL_SESSION_CACHED_CURSORS connection attribute. |
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Size in MB |
Specifies the reclaim buffer maximum size for the replication agent. The replication agent periodically checks to see if the value has changed. The size cannot be greater than the temporary partition size. For more details, see Improving Performance When Reclaiming Memory During Autorefresh Operations in Oracle TimesTen In-Memory Database Cache Guide. |
Result Set
ttDBConfig returns the result set:
| Column | Type | Description |
|---|---|---|
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The name of the specified parameter. |
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The current value of the specified parameter. This is the new value, if you specified a value. |
Examples
To retrieve the current value of the CacheParAwtBatchSize, use:
CALL ttDBConfig('CacheParAwtBatchSize');
<CACHEPARAWTBATCHSIZE, 125>
1 row found.
To set the value of the RepAgentCommitBufSize to 50 MB, use:
CALL ttDBConfig('RepAgentCommitBufSize', '50');
<REPAGENTCOMMITBUFSIZE, 50>
1 row found.
To set the current value of the CacheAgentCommitBufSize to 100, use:
CALL ttDBConfig('CacheAgentCommitBufSize', '100');
< CACHEAGENTCOMMITBUFSIZE, 100 >
1 row found.The following example sets DynamicLoadReduceContention=1:
CALL ttDbConfig('DynamicLoadReduceContention','1');Notes
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After using this built-in procedure to set a parameter value, initiate a checkpoint to ensure the persistence of the parameter change. See details about the
ttCkptprocedure in Checkpoint Operations in Oracle TimesTen In-Memory Database Operations Guide. For details about the checkpoint built-in procedure, see ttCkpt in this chapter. -
Changes to parameter values made by
ttDBConfigcannot be rolled back. -
If you call
ttDBConfigwithout an input parameter, it will return names and values of all supported parameters.
See Also
- Improving AWT Throughput, Configuring Batch Size for Parallel Propagation for AWT Cache Groups, and Improving Performance When Reclaiming Memory During Autorefresh Operations in Oracle TimesTen In-Memory Database Cache Guide.