Note: If you set partition_view_enabled to TRUE, the optimizer will prune (or skip)
Unnecessary table access in partitioned views. This parameter can also change how the cost-based optimizer calculates partitioned view statistics from the underlying table statistics.
Value Range: TRUE | FALSE
Default value: FALSE
Optimizer_max_permutations:
Note: When parsing a query with a large number of joins,
The optimizer will consider limiting the number of exchanges for the table. This helps ensure that the time for parsing the query remains within an acceptable limit,
But the price is not to find the best plan. If the value is less than 1000, you should be able to ensure that the time of each query is only a few seconds or less.
Value range: 4-2^32 (~4.3 G).
Default value: 80,000
Optimizer_index_cost_adj:
Note: You can use to optimize the performance of the optimizer if you consider too many or too few index access paths. The lower the value, the easier it is for the optimizer to select an index. Other words
If you set this value to 50%, the cost of the index access path is half the normal.
Value range: 1-10000
Default value: 100 (general cost of an index access path)
Star_transformation_enabled:
Note: Determine if the cost based query transformation will be applied to the star query. If set to TRUE, the optimizer will consider applying a cost-based conversion to a star query;
If set to FALSE, no conversions are used; If set to Temp_disable, the query conversion is considered, but no temporary tables are used.
Value Range: TRUE | FALSE | Temp_disable
Default value: FALSE
Optimizer_mode:
Description: Specifies the behavior of the optimizer. If set to rule, the Rule-based optimizer is used unless the query contains hints. If set to CHOOSE,
A cost-based optimizer is used unless the table in the statement does not contain statistics. All_rows or First_rows
Always use a cost-based optimization program.
Value range: Rule | CHOOSE | First_rows | All_rows
Default value: CHOOSE
Optimizer_index_caching:
Description: Adjusts the assumed value of the cost-based optimizer,
The percentage of the index block that is expected to be used in the buffer cache for nested loops joins. It affects the cost of nested loops joins that use the index. Set this parameter to a higher value.
You can make nested loops joins less expensive than optimization programs.
Value range: 0-100%.
Default value: 0
Job_queue_processes:
Description: Only for replication environments. It specifies the number of SNP job queue processes per routine (SNP0, ...). SNP9, Snpa, ...
SNPZ). To automatically update a table snapshot or perform a request created by Dbms_job, set the parameter to 1 or greater.
Value range: 0 to 36
Default value: 0
Max_transaction_branches:
Description: Controls the number of branches in distributed transactions. Setting the max_transaction_branches to a lower value can be based on the
Slightly reduce the amount of space in the shared pool. This parameter is deprecated in version 8.1.3.
Value range: 1-32
Default value: 8
Compatible:
Description: Allows you to use a new release, while ensuring backward compatibility with previous versions.
Value range: Default is the current release.
Default value: Determined by release
Archive_lag_target:
Description: This parameter is associated with a time based thread advanced feature.
Value range: 0 or any integer in [60, 7200].
Default value: 0 is the default, and the time based thread advanced feature is disabled. Otherwise, the value will represent the number of seconds
Aq_tm_processes:
Note: When you are greater than 0, time monitoring for queue messages is enabled. This time value can be used to specify the delay and expiration attributes for the message (for application development).
Value range: 0-10
Default value: 0
Tracefile_identifier:
SPFile
Description: Specifies the name of the server parameter file that is currently in use.
Value range: Static parameters
Default value: The SPFILE parameter can be defined in the client PFILE to indicate the name of the server parameter file to use. When the server uses the default server parameter file, the SPFILE value is set internally by the server.
Logmnr_max_persistent_sessions:
Standby_file_management:
Trace_enabled:
IFile:
Description: Used to embed additional parameter files in the current parameter file. You can use this parameter multiple times on more than one row of a parameter file, but there can be only three levels of nesting.
Value range: Any valid parameter file name (syntax is ifile = parameter_file_name).
Default value: NULL
Remote_listener:
Global_context_pool_size:
Description: The amount of memory allocated from the SGA to store and manage the global application environment.
Value range: any integer value.
Default value: 1 M
Plsql_native_library_subdir_count:
Fixed_date:
Description: Sysdate returns the data. For tests that must always return a fixed date rather than a system date,
This value is useful. Use double quotes or do not use quotes. Do not use single quotes.
Value range: Yyyy-mm-dd-hh24:mi:ss (or the default Oracle date format).
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