DBMS_SPM
The DBMS_SPM package supports the SQL plan management feature by providing an interface for the DBA or other user to perform controlled manipulation of plan history and SQL plan baselines maintained for various SQL statements.
This chapter contains the following topics:
See Also: For more information about “Using SQL Plan Management” in the Oracle Database SQL Tuning Guide
DBMS_SPM Overview
The DBMS_SPM package allows the user to manage SQL execution plans using SQL plan management.
SQL plan management prevents performance regressions resulting from sudden changes to the execution plan of a SQL statement by recording and evaluating the execution plans of SQL statements over time, and builds SQL plan baselines composed of a set of existing plans known to be efficient. The SQL plan baselines are then used to preserve performance of corresponding SQL statements, regardless of changes occurring in the system. Common usage scenarios where SQL plan management can improve or preserve SQL performance include:
-
A database upgrade that installs a new optimizer version usually results in plan changes for a small percentage of SQL statements, with most of the plan changes resulting in either no performance change or improvement. However, certain plan changes may cause performance regressions. The use of SQL plan baselines significantly minimizes potential performance regressions resulting from a database upgrade.
-
Ongoing system and data changes can impact plans for some SQL statements, potentially causing performance regressions. The use of SQL plan baselines helps to minimize performance regressions and stabilize SQL performance.
-
Deployment of new application modules means introducing new SQL statements into the system. The application software may use appropriate SQL execution plans developed under a standard test configuration for the new SQL statements. If the system production configuration differs significantly from the test configuration, SQL plan baselines can be evolved over time to produce better performance.
DBMS_SPM Security Model
The package is owned by SYS. The EXECUTE package privilege is required to execute its procedures. Any user granted the ADMINISTER SQL MANAGEMENT OBJECT privilege is able to execute the DBMS_SPM package.
DBMS_SPM Constants
The DBMS_SPM package provides constants that can be used for specifying parameter values.
These are shown in the following table. These constants are defined as standard input for the time_limit parameter of the EVOLVE_SQL_PLAN_BASELINE Function.
Table 1 DBMS_SPM Constants
| Constant | Type | Value | Description |
|---|---|---|---|
AUTO_LIMIT |
INTEGER |
2147483647 |
Oracle determines the appropriate time spent by the EVOLVE_SQL_PLAN_BASELINE Function. |
NO_LIMIT |
INTEGER |
2147483647 -1 |
There is no limit to the time spent by the EVOLVE_SQL_PLAN_BASELINE Function. |
DBMS_SPM Examples
These examples will help you understand use of DBMS_SPM.
Detailed examples are located under the following topics:
DBMS_SPM Data Structures
The DBMS_SPM package defines a TABLE type.
Table Types
DBMS_SPM NAMELIST Table Type
This type allows for a list of names as an input parameter.
Syntax
TYPE name_list IS TABLE OF VARCHAR2(30);
Summary of DBMS_SPM Subprograms
This table lists and briefly describes the DBMS_SPM package subprograms.
Table 2 DBMS_SPM Package Subprograms
| Subprogram | Description |
|---|---|
| ACCEPT_SQL_PLAN_BASELINE Procedure | Accepts a plan based on the recommendation of an evolve task |
| ADD_VERIFIED_SQL_PLAN_BASELINE Function | Finds the plans available for the given SQL_ID in different sources such Cursor Cache, Auto SQL Tuning Set, and Automatic Workload Repository. |
| ALTER_SQL_PLAN_BASELINE Function | Changes an attribute of a single plan or all plans associated with a SQL statement using the attribute name/value format |
| CANCEL_EVOLVE_TASK Procedure | Cancels a currently executing evolve task |
| CONFIGURE Procedure | Sets configuration options for SQL management base, in parameter/value format |
| CREATE_EVOLVE_TASK Function | Creates an advisor task and sets its parameters |
| CREATE_STGTAB_BASELINE Procedure | Creates a staging table that used for transporting SQL plan baselines from one system to another |
| DROP_EVOLVE_TASK Procedure | Drops an evolved task |
| DROP_MIGRATED_STORED_OUTLINE Function | Drops all stored outlines that have been migrated to SQL plan baselines. |
| DROP_SQL_PLAN_BASELINE Function | Drops a single plan, or all plans associated with a SQL statement |
| EVOLVE_SQL_PLAN_BASELINE Function | Evolves SQL plan baselines associated with one or more SQL statements |
| EXECUTE_EVOLVE_TASK Function | Executes a previously created evolve task |
| INTERRUPT_EVOLVE_TASK Procedure | Interrupts a currently executing evolve task |
| LOAD_PLANS_FROM_CURSOR_CACHE Functions | Loads one or more plans present in the cursor cache for a SQL statement |
| LOAD_PLANS_FROM_AWR Function | Loads the SQL Management Base (SMB) with SQL plan baselines for a set of SQL statements using the plans from the AWR, and returns the number of plans loaded |
| LOAD_PLANS_FROM_SQLSET Function | Loads plans stored in a SQL tuning set (STS) into SQL plan baselines |
| MIGRATE_STORED_OUTLINE Functions | Migrates existing stored outlines to SQL plan baselines |
| PACK_STGTAB_BASELINE Function | Packs (exports) SQL plan baselines from SQL management base into a staging table |
| RESET_EVOLVE_TASK Procedure | Resets an evolve task to its initial state |
| RESUME_EVOLVE_TASK Procedure | Resumes a previously interrupted task |
| REPORT_AUTO_EVOLVE_TASK Function | Displays the results of an execution of an automatic evolve task. |
| REPORT_EVOLVE_TASK Function | Displays the results of an evolved task |
| SET_EVOLVE_TASK_PARAMETER Procedure | Sets a parameter of an evolve task |
| UNPACK_STGTAB_BASELINE Function | Unpacks (imports) SQL plan baselines from a staging table into SQL management base |
ACCEPT_SQL_PLAN_BASELINE Procedure
The procedure accepts a plan based on the recommendation of an evolve task.
Syntax
DBMS_SPM.ACCEPT_SQL_PLAN_BASELINE (
task_name IN VARCHAR2,
object_id IN NUMBER := NULL,
task_owner IN VARCHAR2 := NULL,
force IN BOOLEAN := FALSE);
Parameters
Table 3 ACCEPT_SQL_PLAN_BASELINE Procedure Parameters
| Parameter | Description |
|---|---|
task_name |
Identifier of task to implement |
object_id |
Identifier of the advisor framework object that represents a single plan. If NULL, the report is generated for all objects. |
task_owner |
Owner of the evolve task. Defaults to the current schema owner. |
force |
Accept the plan even if the advisor did not recommend such an action. The default is FALSE requiring acceptance of the plan only if the plan is verified and shows sufficient improvement in benefit. |
ADD_VERIFIED_SQL_PLAN_BASELINE Function
This function finds the plans available for the given SQL_ID in different sources such Cursor Cache, Auto SQL Tuning Set, and Automatic Workload Repository.
Syntax
DBMS_SPM.ADD_VERIFIED_SQL_PLAN_BASELINE (
sql_id IN VARCHAR2
);
Parameters
Table 4 ADD_VERIFIED_SQL_PLAN_BASELINE Function
| Parameter | Description |
|---|---|
sql_id |
The SQL statement identifier, which is used to identify the plans in different sources, such as the cursor cache. |
Return Value
A CLOB containing a report of SQL plan baselines verified, reproduced and accepted.
Usage Notes
SQL plan baselines are created to ensure that the best-known plans are used for the selected SQL statement. These are the steps that the function executes:
-
Loads plans from Cursor Cache, Automatic Workload Repository, and Auto SQL Tuning Set (
SYS_AUTO_STS) into SQL Plan Management SQL plan history in a non-accepted state. -
Uses the SQL Plan Management Evolve Advisor internally to identify the best-performing execution plans. The best-performing plans are accepted.
Note: “Administer SQL Management Object” privilege. is required.
Examples
Example 1: A SQL statement with SQL ID 36k32wnz0v0fd is in the Cursor Cache with plan hash value 923079310 (this plan is an index unique scan).
select sql_id, plan_hash_value, sql_text
from v$sql
where sql_text like 'select /* SPM_TEST_QUERY%'
/
SQL_ID PLAN_HASH_VALUE SQL_TEXT
--------------- --------------- --------------------------------------------------------------------
36k32wnz0v0fd 923079310 select /* SPM_TEST_QUERY */ num from example_spm_table where id = 100
Example 2: The Automatic SQL Tuning Set has captured two different plans - the index unique scan (923079310) and a Full Table Scan (2448381833).
select sql_text, sqlset_name, plan_hash_value
from dba_sqlset_statements
where sql_text like 'select /* SPM_TEST_QUERY%';
SQL_TEXT SQLSET_NAME PLAN_HASH_VALUE
----------------------------------------------------------------------- ------------- ---------------
select /* SPM_TEST_QUERY */ num from example_spm_table where id = 100 SYS_AUTO_STS 923079310
select /* SPM_TEST_QUERY */ num from example_spm_table where id = 100 SYS_AUTO_STS 2448381833
Example 3: Ask SQL Plan Management to create a SQL plan baseline for the best execution plan.
set tab off
set serveroutput on
set pagesize 100
set linesize 250
set long 100000
column report format a200
var rep clob;
BEGIN
:rep := DBMS_SPM. ADD_VERIFIED_SQL_PLAN_BASELINE('36k32wnz0v0fd');
END;
/
select :rep report from dual;
SQL Plan Baselines verified for SQL ID: 36k32wnz0v0fd
------------------------------------------------------------------------------------------
Plan Hash Value Plan Name Reproduced Accepted Source
--------------- ------------------------------ ---------- -------- --------------
923079310 SQL_PLAN_163tr5qgzwmgt05ce4c2e YES YES CURSOR CACHE
2448381833 SQL_PLAN_163tr5qgzwmgt1f191f3e YES NO SQL TUNING SET
-----------------------------------------------------------------------------------------
SQL Handle : SQL_130f372d9ffe4df9
SQL Text : select /* SPM_TEST_QUERY */ num from example_spm_table where id = 100
-----------------------------------------------------------------------------------------
Example 4: Confirm that an SQL plan baseline has been accepted.
select sql_text, accepted, enabled, sql_handle, plan_name
from dba_sql_plan_baselines
where sql_text like 'select /* SPM_TEST_QUERY%';
SQL_TEXT ACC ENA SQL_HANDLE PLAN_NAME
---------------------------------------------------------------------- --- --- -------------------- ------------------------------
select /* SPM_TEST_QUERY */ num from example_spm_table where id = 100 YES YES SQL_130f372d9ffe4df9 SQL_PLAN_163tr5qgzwmgt05ce4c2e
select /* SPM_TEST_QUERY */ num from example_spm_table where id = 100 NO YES SQL_130f372d9ffe4df9 SQL_PLAN_163tr5qgzwmgt1f191f3e
Example 5: View the accepted and non-accepted plans.
select * from table(dbms_xplan.display_sql_plan_baseline('SQL_130f372d9ffe4df9'));
--------------------------------------------------------------------------------
SQL handle: SQL_130f372d9ffe4df9
SQL text: select /* SPM_TEST_QUERY */ num from example_spm_table where id = 100
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
Plan name: SQL_PLAN_163tr5qgzwmgt05ce4c2e Plan id: 923079310
Enabled: YES Fixed: NO Accepted: YES Origin: EVOLVE-LOAD-FROM-CURSOR-CACHE
Plan rows: From Auto SQL Tuning Set
--------------------------------------------------------------------------------
Plan hash value: 923079310
-------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
-------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 2 (100)| |
| 1 | TABLE ACCESS BY INDEX ROWID| EXAMPLE_SPM_TABLE | 1 | 8 | 2 (0)| 00:00:01 |
|* 2 | INDEX UNIQUE SCAN | SPM_TAB_PK | 1 | | 1 (0)| 00:00:01 |
-------------------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("ID"=100)
--------------------------------------------------------------------------------
Plan name: SQL_PLAN_163tr5qgzwmgt1f191f3e Plan id: 2448381833
Enabled: YES Fixed: NO Accepted: NO Origin: EVOLVE-LOAD-FROM-STS
Plan rows: From Auto SQL Tuning Set
--------------------------------------------------------------------------------
Plan hash value: 2448381833
---------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
---------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 3 (100)| |
|* 1 | TABLE ACCESS FULL| EXAMPLE_SPM_TABLE | 1 | 8 | 3 (0)| 00:00:01 |
---------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
1 - filter("ID"=100)
ALTER_SQL_PLAN_BASELINE Function
This function changes an attribute of a single plan or all plans associated with a SQL statement using the attribute name/value format.
Syntax
DBMS_SPM.ALTER_SQL_PLAN_BASELINE (
sql_handle IN VARCHAR2 := NULL,
plan_name IN VARCHAR2 := NULL,
attribute_name IN VARCHAR2,
attribute_value IN VARCHAR2)
RETURN PLS_INTEGER;
Parameters
Table 5 ALTER_SQL_PLAN_BASELINE Function Parameters
| Parameter | Description |
|---|---|
sql_handle |
SQL statement handle. It identifies plans associated with a SQL statement for an attribute change. If NULL then plan_name must be specified. |
plan_name |
Name of a specific plan. Default NULL means set the attribute for all plans associated with a SQL statement identified by sql_handle. If NULL then sql_handle must be specified. |
attribute_name |
Name of the plan attribute to set (see table below). |
attribute_value |
Value of the plan attribute to use (see table below) |
Table 6 Names & Values for ALTER_SQL_PLAN_BASELINE Function Parameters
| Name | Description | Possible Values |
|---|---|---|
enabled |
‘YES’ means the plan is available for use by the optimizer. It may or may not be used, depending on accepted status. |
‘YES’ or ‘NO’ |
fixed |
‘YES’ means the SQL plan baseline is not evolved over time. A fixed plan takes precedence over a non-fixed plan. |
‘YES’ or ‘NO’ |
autopurge |
‘YES’ means the plan is purged if it is not used for a time period. ‘NO’ means it is never purged. |
‘YES’ or ‘NO’ |
plan_name |
Name of the plan | String of up to 30 characters |
description |
Plan description. | String of up to 500 bytes |
Return Values
The number of plans altered.
Usage Notes
When a single plan is specified, one of the various statuses, or plan name, or description can be altered. When all plans for a SQL statement are specified, one of various statuses, or description can be altered. This function can be called numerous times, each time setting a different plan attribute of same plan(s) or different plan(s).
CANCEL_EVOLVE_TASK Procedure
The procedure cancels a currently executing evolve task. All intermediate results are removed from the task.
Syntax
DBMS_SPM.CANCEL_EVOLVE_TASK (
task_name IN VARCHAR2);
Parameters
Table 7 CANCEL_EVOLVE_TASK Procedure Parameters
| Parameter | Description |
|---|---|
task_name |
Identifier of task to cancel |
CONFIGURE Procedure
This procedure sets configuration options for the SQL management base and for the maintenance of SQL plan baselines. You can call this function multiple times, setting a different configuration option each time.
Syntax
DBMS_SPM.CONFIGURE (
parameter_name IN VARCHAR2,
parameter_value IN VARCHAR2 := NULL,
allow IN BOOLEAN := TRUE);
Parameters
Table 8 CONFIGURE Procedure Parameters
| Parameter | Description |
|---|---|
parameter_name |
Name of parameter to set (see table below). |
parameter_value |
Value of parameter to use (see table below). The maximum length of parameter_value is 1000 characters. |
allow |
Whether to include (true) or exclude (false) matching SQL statements and plans for theauto_capture_* parameters. If null, then the procedure ignores the specified parameter. |
Table 9 Names and Values for CONFIGURE Procedure Parameters
| Parameter Name | Description | Possible Values |
|---|---|---|
auto_capture_action |
Action to include (=) or exclude (<>) for SQL plan management automatic capture, depending on whether allow is TRUE or FALSE. A null value removes the filter for parameter_name entirely. |
Action name, for example, R% |
auto_capture_module |
Module to include ( The database only uses this filter when |
Module name, for example, LOGGER |
auto_capture_parsing_schema_name |
Parsing schema to include ( The database only uses this filter when |
Schema name, for example, HR |
auto_capture_sql_text |
Search pattern to apply to SQL text of The database only uses this filter when |
Text of a SQL statement, for example, SELECT a% |
auto_spm_evolve_task |
Setting to enable or disable the high-frequency SPM Evolve Advisor task.
Note: See About Automatic SQL Plan Management in the Oracle Database SQL Tuning Guide, which discusses the high frequency SPM Evolve task and explains the difference between real-time and background-verified Automatic SQL Plan Management. |
ON, OFF, AUTO |
plan_retention_weeks |
Number of weeks to retain unused plans before the database purges them. A null value resets to the default value of 53 weeks, or 1 year plus 1 week. (This retains plans for annually executing queries.) The value of |
5-523 (default is 53) |
space_budget_percent |
Maximum percent of The database issues alerts when this amount is exceeded. A null value resets the percentage to the default value of 10%. The value of |
1-50 (default is 10) |
Exceptions
Table 10 CONFIGURE Exceptions
| Error Number | Description |
|---|---|
ORA-38133 |
Invalid parameter name |
ORA-38134 |
Invalid parameter value |
ORA-38150 |
Not enough space for new filter |
ORA-38151 |
Module name too long |
ORA-38152 |
Action name too long |
ORA-38304 |
Missing or invalid user name |
Usage Notes
-
When
parameter_nameisauto_capture_sql_text, theparameter_valueis an automatic search filter. The filter uses the search pattern ofLIKEparameter_namewhenallow=>true. The filter uses the patternNOT LIKEparameter_namewhenallow=>false.For all other non-null
parameter_namevalues, the search pattern depends on theallowsetting. The parameter uses an equal sign (=) whenallow=>true. The parameter uses a not-equal sign (<>) whenallow=>false. -
You can configure multiple automatic capture parameters of different types. You cannot specify multiple values for the same parameter. Instead, the values specified for a particular parameter are combined. For example, specifying
auto_capture_sql_textto be ‘%TABLE1%’,TRUE, and ‘%TABLE2%’,FALSEwill result in matching SQL textLIKE '%TABLE1%'andNOT LIKE '%TABLE2%'. The database uses these configuration settings only when the initialization parameterOPTIMIZER_CAPTURE_SQL_PLAN_BASELINESis set toTRUE. -
A null value for
parameter_valueremoves the filter forparameter_nameentirely. By usingparamter_value=>'%'in combination withallow=FALSE, you can filter out all values for a parameter, and then create a separate filter to include only specified values. TheDBA_SQL_MANAGEMENT_CONFIGview shows the current filters. -
The default space budget for SQL management base is no more than ten percent of the size of
SYSAUXtablespace. The space budget can be set to a maximum of 50%. The default unused plan retention period is one year and one week, which means a plan will be automatically purged if it has not been used for more than a year. The retention period can be set to a maximum of 523 weeks (i.e. a little over 10 years). -
When the space occupied by SQL management base exceeds the defined space budget limit, a weekly database alert is generated.
Examples
The following example creates a filter for SQL text that is like SELECT a%:
EXEC DBMS_SPM.CONFIGURE('AUTO_CAPTURE_SQL_TEXT', 'select a%', 'TRUE');
The following example filters out the HR parsing schema:
EXEC DBMS_SPM.CONFIGURE('AUTO_CAPTURE_PARSING_SCHEMA_NAME', 'HR', 'FALSE');
The following example removes any existing filters for SQL text:
EXEC DBMS_SPM.CONFIGURE('AUTO_CAPTURE_SQL_TEXT', NULL, NULL);
The following example removes any LIKE or NOT LIKE filters for the SQL text select a%:
EXEC DBMS_SPM.CONFIGURE('AUTO_CAPTURE_SQL_TEXT', 'select a%', NULL);
The following example creates a filter with the predicate (action LIKE 'R%') OR (action LIKE '%E_'):
EXEC DBMS_SPM.CONFIGURE('AUTO_CAPTURE_ACTION', 'R%', 'TRUE');
EXEC DBMS_SPM.CONFIGURE('AUTO_CAPTURE_ACTION', '%E_', 'TRUE');
The following example creates a filter with the predicate NOT(module LIKE 'LOGGER') AND NOT(module LIKE 'UTIL__'):
EXEC DBMS_SPM.CONFIGURE('AUTO_CAPTURE_MODULE', 'LOGGER', 'FALSE');
EXEC DBMS_SPM.CONFIGURE('AUTO_CAPTURE_MODULE', 'UTIL__', 'FALSE');
CREATE_EVOLVE_TASK Function
The function has two overloads, both of which create an advisor task and sets its parameters. This version which takes a SQL handle creates an evolve task in order to evolve one or more plans for a given SQL statement.
Syntax
DBMS_SPM.CREATE_EVOLVE_TASK (
sql_handle IN VARCHAR2 := NULL,
plan_name IN VARCHAR2 := NULL,
time_limit IN NUMBER := DBMS_SPM.AUTO_LIMIT,
task_name IN VARCHAR2 := NULL,
description IN VARCHAR2 := NULL)
RETURN VARCHAR2;
DBMS_SPM.CREATE_EVOLVE_TASK (
plan_list IN DBMS_SPM.NAME_LIST,
time_limit IN NUMBER := DBMS_SPM.AUTO_LIMIT,
task_name IN VARCHAR2 := NULL,
description IN VARCHAR2 := NULL)
RETURN VARCHAR2;
Parameters
Table 11 CREATE_EVOLVE_TASK Function Parameters
| Parameter | Description |
|---|---|
sql_handle |
Handle of a SQL statement. The default NULL considers all SQL statements with non-accepted plans. |
plan_list |
List of plan names. The plans may belong to different SQL statements. |
plan_name |
Plan identifier. The default NULL considers all non-accepted plans of the specified SQL handle or all SQL statements if the SQL handle is NULL. |
time_limit |
Time limit in number of minutes. The time limit is global and it is used in the following manner. The time limit for first non-accepted plan is equal to the input value. The time limit for the second non-accepted plan is equal to (input value - time spent in first plan verification) and so on. The default DBMS_SPM.AUTO_LIMIT means let the system choose an appropriate time limit based on the number of plan verifications required to be done. The value DBMS_SPM.NO_LIMIT means no time limit. |
task_name |
Evolve task name |
description |
Description of the task (maximum 256 characters) |
Return Values
SQL evolve task unique name
CREATE_STGTAB_BASELINE Procedure
This procedure creates a staging table used for transporting SQL plan baselines from one system to another.
Syntax
DBMS_SPM.CREATE_STGTAB_BASELINE (
table_name IN VARCHAR2,
table_owner IN VARCHAR2 := NULL,
tablespace_name IN VARCHAR2 := NULL);
Parameters
Table 12 CREATE_STGTAB_BASELINE Procedure Parameters
| Parameter | Description |
|---|---|
table_name |
Name of staging table to create for the purpose of packing and unpacking SQL plan baselines |
table_owner |
Name of owner of the staging table. The default, NULL, means that the current schema is the table owner. |
tablespace_name |
Name of the tablespace. The default, NULL, results in creating the staging table in the default tablespace. |
Usage Notes
The creation of staging table is the first step. To migrate SQL plan baselines from one system to another, the user or DBA has to perform a series of steps as follows:
-
Create a staging table in the source system
-
Select SQL plan baselines in the source system and pack them into the staging table
-
Copy the staging table from the source system to the target system. For example, you can use Oracle Data Pump to export and import the staging table.
-
Select SQL plan baselines from the staging table and unpack them into the target system
DROP_EVOLVE_TASK Procedure
The procedure drops an evolved task.
Syntax
DBMS_SPM.DROP_EVOLVE_TASK (
task_name IN VARCHAR2);
Parameters
Table 13 DROP_EVOLVE_TASK Procedure Parameters
| Parameter | Description |
|---|---|
task_name |
Identifier of the task that you want to drop |
DROP_MIGRATED_STORED_OUTLINE Function
This function drops all stored outlines that have been migrated to SQL plan baselines.
Syntax
DBMS_SPM.DROP_MIGRATED_STORED_OUTLINE ()
RETURN PLS_INTEGER;
Requires the following privileges:
-
Administer SQL Management Object -
DROP ANY OUTLINE -
select on dba_outlines
Return Values
The number of outlines dropped.
DROP_SQL_PLAN_BASELINE Function
This function drops a single plan, or all plans associated with a SQL statement.
Syntax
DBMS_SPM.DROP_SQL_PLAN_BASELINE (
sql_handle IN VARCHAR2 := NULL,
plan_name IN VARCHAR2 := NULL)
RETURN PLS_INTEGER;
Parameters
Table 14 DROP_SQL_PLAN_BASELINE Function Parameters
| Parameter | Description |
|---|---|
sql_handle |
SQL statement handle. It identifies plans associated with a SQL statement that are to be dropped. If NULL then plan_name must be specified. |
plan_name |
Plan name. It identifies a specific plan. Default NULL means to drop all plans associated with the SQL statement identified by sql_handle. |
Return Values
The number of plans dropped
EVOLVE_SQL_PLAN_BASELINE Function
This function evolves SQL plan baselines associated with one or more SQL statements. A SQL plan baseline is evolved when one or more of its non-accepted plans is changed to an accepted plan or plans.
If interrogated by the user (parameter verify = ‘YES’), the execution performance of each non-accepted plan is compared against the performance of a plan chosen from the associated SQL plan baseline. If the non-accepted plan performance is found to be better than SQL plan baseline performance, the non-accepted plan is changed to an accepted plan provided such action is permitted by the user (parameter commit = ‘YES’).
The second form of the function employs a plan list format.
Syntax
DBMS_SPM.EVOLVE_SQL_PLAN_BASELINE (
sql_handle IN VARCHAR2 := NULL,
plan_name IN VARCHAR2 := NULL,
time_limit IN INTEGER := DBMS_SPM.AUTO_LIMIT,
verify IN VARCHAR2 := 'YES',
commit IN VARCHAR2 := 'YES')
RETURN CLOB;
DBMS_SPM.EVOLVE_SQL_PLAN_BASELINE (
plan_list IN DBMS_SPM.NAME_LIST,
time_limit IN INTEGER := DBMS_SPM.AUTO_LIMIT,
verify IN VARCHAR2 := 'YES',
commit IN VARCHAR2 := 'YES')
RETURN CLOB;
Parameters
Table 15 EVOLVE_SQL_PLAN_BASELINE Function Parameters
| Parameter | Description |
|---|---|
sql_handle |
SQL statement identifier. Unless plan_name is specified, NULL means to consider all statements with non-accepted plans in their SQL plan baselines. |
plan_name |
Plan identifier. Default NULL means to consider all non- accepted plans in the SQL plan baseline of either the identified SQL statement or all SQL statements if sql_handle is NULL. |
plan_list |
A list of plan names. Each plan in the list can belong to same or different SQL statement. |
time_limit |
Time limit in number of minutes. This applies only if
|
verify |
Specifies whether to execute the plans and compare the performance before changing non-accepted plans into accepted plans. A performance verification involves executing a non-accepted plan and a plan chosen from corresponding SQL plan baseline and comparing their performance statistics. If non-accepted plan shows performance improvement, it is changed to an accepted plan.
|
commit |
Specifies whether to update the
|
Return Values
A CLOB containing a formatted text report showing non-accepted plans in sequence, each with a possible change of its ACCEPTED status, and if verify = ‘YES’ the result of their performance verification.
Usage Notes
Invoking this subprogram requires the ADMINISTER SQL MANAGEMENT OBJECT privilege.
EXECUTE_EVOLVE_TASK Function
The function executes a previously created evolve task.
Syntax
DBMS_SPM.EXECUTE_EVOLVE_TASK (
task_name IN VARCHAR2,
execution_name IN VARCHAR2 := NULL,
execution_desc IN VARCHAR2 := NULL);
RETURN VARCHAR2;
Parameters
Table 16 EXECUTE_EVOLVE_TASK Function Parameters
| Parameter | Description |
|---|---|
task_name |
Evolve task name |
execution_name |
Name to qualify and identify an execution. If not specified, it is generated by the advisor and returned by the function. |
execution_desc |
Description of the execution (maximum 256 characters) |
Return Values
Name of the new execution
INTERRUPT_EVOLVE_TASK Procedure
The procedure interrupts a currently executing evolve task. The task ends its operations as at a normal exit and the user can access the intermediate results. The task can be resumed later.
Syntax
DBMS_SPM.INTERRUPT_EVOLVE_TASK (
task_name IN VARCHAR2);
Parameters
Table 17 INTERRUPT_EVOLVE_TASK Procedure Parameters
| Parameter | Description |
|---|---|
task_name |
Identifier of task to interrupt |
LOAD_PLANS_FROM_AWR Function
This function loads the SQL Management Base (SMB) with SQL plan baselines for a set of SQL statements using the plans from the AWR, and returns the number of plans loaded.
Syntax
DBMS_SPM.LOAD_PLANS_FROM_AWR
begin_snap IN NUMBER,
end_snap IN NUMBER,
basic_filter IN VARCHAR2 := NULL,
fixed IN VARCHAR2 := 'NO',
enabled IN VARCHAR2 := 'YES',
commit_rows IN NUMBER := 1000)
RETURN PLS_INTEGER;
Parameters
Table 18 LOAD_PLANS_FROM_AWR Function Parameters
| Parameter | Description |
|---|---|
begin_snap |
Begin snapshot |
end_snap |
End snapshot |
basic_filter |
SQL predicate to filter the SQL from AWR. Specifies the SQL predicate that filters the SQL from the shared SQL area defined on attributes of the |
fixed |
Default 'NO' means the loaded plans will not change the current ‘fixed’ property of the SQL plan baseline into which they are loaded. |
enabled |
Default 'YES' means the loaded plans will be considered by the optimizer |
commit_rows |
Number of SQL plans to load before doing a periodic commit. |
dbid |
The DBID that is used for imported or PDB-level AWR data. |
Usage Notes
Requires the Administer SQL Management Object privilege
See Also: For information on the SQLSET_ROW objects, see SQLSET_ROW Object Type.
LOAD_PLANS_FROM_CURSOR_CACHE Functions
This function loads one or more plans present in the cursor cache for a SQL statement, or a set of SQL statements. It has four overloads: using SQL statement text, using SQL handle, using SQL ID, or using attribute_name and attribute_value pair.
Syntax
DBMS_SPM.LOAD_PLANS_FROM_CURSOR_CACHE (
sql_id IN VARCHAR2,
plan_hash_value IN NUMBER := NULL,
sql_text IN CLOB,
fixed IN VARCHAR2 := 'NO',
enabled IN VARCHAR2 := 'YES')
RETURN PLS_INTEGER;
DBMS_SPM.LOAD_PLANS_FROM_CURSOR_CACHE (
sql_id IN VARCHAR2,
plan_hash_value IN NUMBER := NULL,
sql_handle IN VARCHAR2,
fixed IN VARCHAR2 := 'NO',
enabled IN VARCHAR2 := 'YES')
RETURN PLS_INTEGER;
DBMS_SPM.LOAD_PLANS_FROM_CURSOR_CACHE (
sql_id IN VARCHAR2,
plan_hash_value IN NUMBER := NULL,
fixed IN VARCHAR2 := 'NO',
enabled IN VARCHAR2 := 'YES')
RETURN PLS_INTEGER;
DBMS_SPM.LOAD_PLANS_FROM_CURSOR_CACHE (
attribute_name IN VARCHAR2,
attribute_value IN VARCHAR2,
fixed IN VARCHAR2 := 'NO',
enabled IN VARCHAR2 := 'YES')
RETURN PLS_INTEGER;
Parameters
Table 19 LOAD_PLANS_FROM_CURSOR_CACHE Function Parameters
| Parameter | Description |
|---|---|
sql_id |
SQL statement identifier. Identifies a SQL statement in the cursor cache. Note: In the third overload the text of identified SQL statement is extracted from cursor cache and is used to identify the SQL plan baseline into which the plan(s) are loaded. If the SQL plan baseline doesn’t exist it is created. |
plan_hash_value |
Plan identifier. Default NULL means capture all plans present in the cursor cache for the SQL statement identified by SQL_ID. |
sql_text |
SQL text to use in identifying the SQL plan baseline into which the plans are loaded. If the SQL plan baseline does not exist, it is created. The use of text is crucial when the user tunes a SQL statement by adding hints to its text and then wants to load the resulting plan(s) into the SQL plan baseline of the original SQL statement. |
sql_handle |
SQL handle to use in identifying the SQL plan baseline into which the plans are loaded. The sql_handle must denote an existing SQL plan baseline. The use of handle is crucial when the user tunes a SQL statement by adding hints to its text and then wants to load the resulting plan(s) into the SQL plan baseline of the original SQL statement. |
fixed |
Default 'NO' means the loaded plans are used as non-fixed plans. Value 'YES' means the loaded plans are used as fixed plans and the SQL plan baseline will not be evolved over time. |
attribute_name |
One of possible attribute names:
|
attribute_value |
Attribute value is used as a search pattern of LIKE predicate if attribute name is 'SQL_TEXT'. Otherwise, it is used as an equality search value. (for example, for specifying attribute_name => 'SQL_TEXT', and attribute_value => '% HR-123 %' means applying SQL_TEXT LIKE '% HR-123 %' as a selection filter. Similarly, specifying attribute_name => 'MODULE', and attribute_value => 'HR' means applying 'MODULE = ‘HR' as a plan selection filter). The attribute value is upper-cased except when it is enclosed in double quotes or attribute name is 'SQL_TEXT'. |
enabled |
Default ‘YES’ means the loaded plans are enabled for use by the optimizer |
Return Values
Number of plans loaded
Usage Notes
Invoking this subprogram requires the ADMINISTER SQL MANAGEMENT OBJECT privilege.
LOAD_PLANS_FROM_SQLSET Function
This function loads plans stored in a SQL tuning set (STS) into SQL plan baselines. The plans loaded from STS are not verified for performance but added as accepted plans to existing or new SQL plan baselines. This function can be used to seed SQL management base with new SQL plan baselines.
Syntax
DBMS_SPM.LOAD_PLANS_FROM_SQLSET (
sqlset_name IN VARCHAR2,
sqlset_owner IN VARCHAR2 := NULL,
basic_filter IN VARCHAR2 := NULL,
fixed IN VARCHAR2 := 'NO',
enabled IN VARCHAR2 := 'YES'
commit_rows IN NUMBER := 1000)
RETURN PLS_INTEGER;
Parameters
Table 20 LOAD_PLANS_FROM_SQLSET Function Parameters
| Parameter | Description |
|---|---|
sqlset_name |
Name of the STS from where the plans are loaded into SQL plan baselines |
sqlset_owner |
Owner of STS. NULL means current schema is the owner. |
basic_filter |
A filter applied to the STS to select only qualifying plans to be loaded. The filter can take the form of any WHERE clause predicate that can specified against the view DBA_SQLSET_STATEMENTS. For example basic_filter => ‘sql_text like ''select /*LOAD_STS*/%''' or basic_filter => 'sql_id=''b62q7nc33gzwx'''. |
fixed |
Default ‘NO’ means the loaded plans are used as non-fixed plans. Value ‘YES’ means the loaded plans are used as fixed plans and the SQL plan baseline will not be evolved over time. |
enabled |
Default ‘YES’ means the loaded plans are enabled for use by the optimizer |
commit_rows |
Number of SQL plans to load before doing a periodic commit. This helps to shorten the undo log. |
Return Values
The number of plans loaded
Usage Notes
-
To load plans from a remote system, first load the plans into an STS on the remote system, export/import the STS from remote to local system, and then use this function.
-
To load plans from Automatic Workload Repository (AWR), first load the plans stored in AWR snapshots into an STS, and then use this procedure.
-
The user can also capture plans resident in the cursor cache for one or more SQL statements into an STS, and then use this procedure.
MIGRATE_STORED_OUTLINE Functions
This function migrates stored outlines for one or more SQL statements to plan baselines in the SQL management base (SMB). Users can specify which stored outline(s) to be migrated based on outline name, SQL text, or outline category, or migrate all stored outlines in the system to SQL plan baselines.
This second overload of the function migrates stored outlines for one or more SQL statements to plan baselines in the SQL management base (SMB) given one or more outline names.
Syntax
DBMS_SPM.MIGRATE_STORED_OUTLINE (
attribute_name IN VARCHAR2,
attribute_value IN CLOB,
fixed IN VARCHAR2 := 'NO')
RETURN CLOB;
DBMS_SPM.MIGRATE_STORED_OUTLINE (
outln_list IN DBMS_SPM.NAME_LIST,
fixed IN VARCHAR2 := 'NO')
RETURN CLOB;
Parameters
Table 21 MIGRATE_STORED_OUTLINE Function Parameters
| Parameter | Description |
|---|---|
attribute_name |
Specifies the type of parameter used in
|
attribute_value |
Based on
|
fixed |
NO (default) or YES. Specifies the “fixed” status of the plans generated during migration. By default, plans are generated as “non-fixed” plans. |
outln_list |
List of outline names to be migrated |
Return Values
A CLOB containing a formatted report to describe the statistics during the migration, including:
-
Number of stored outlines successfully migrated
-
Number of stored outlines (and also the corresponding outline names) failed to be migrated and the reasons for the failure
Usage Note
-
When the user specifies an outline name, the function migrates stored outlines to plan baseline based on given outline name, which uniquely identifies a single stored outline to be migrated.
-
When the user specifies SQL text, the function migrates all stored outlines created for a given SQL statement. A single SQL statement can have multiple stored outlines created for it under different category names. One plan baseline plan is created for each stored outline. The new plan baselines have category names set to
DEFAULT. The module name of a plan baseline is set to be the same as the stored outline. -
When the user specifies a category name, the function migrates all stored outlines with the given category name. Only one stored outline exists per category per SQL statement. One plan baseline is created for each stored outline.
-
When user specifies to migrate
all, the function migrates all stored outlines in the system to plan baselines. One plan baseline is created for each stored outline.
PACK_STGTAB_BASELINE Function
This function packs (exports) SQL plan baselines from SQL management base into a staging table.
Syntax
DBMS_SPM.PACK_STGTAB_BASELINE (
table_name IN VARCHAR2,
table_owner IN VARCHAR2 := NULL,
sql_handle IN VARCHAR2 := NULL,
plan_name IN VARCHAR2 := NULL,
sql_text IN CLOB := NULL,
creator IN VARCHAR2 := NULL, origin IN VARCHAR2 := NULL,
enabled IN VARCHAR2 := NULL,
accepted IN VARCHAR2 := NULL,
fixed IN VARCHAR2 := NULL,
module IN VARCHAR2 := NULL,
action IN VARCHAR2 := NULL)
RETURN NUMBER;
Parameters
Table 22 PACK_STGTAB_BASELINE Function Parameters
| Parameter | Description |
|---|---|
table_name |
Name of staging table into which SQL plan baselines are packed (case insensitive unless double quoted) |
table_owner |
Name of staging table owner.Default NULL means current schema is the table owner |
sql_handle |
SQL handle (case sensitive) |
plan_name |
Plan name (case sensitive, % wildcards accepted) |
sql_text |
SQL text string (case sensitive, % wildcards accepted) |
creator |
Creator of SQL plan baseline (case insensitive unless double quoted) |
origin |
Origin of SQL plan baseline, should be 'MANUAL-LOAD', 'AUTO-CAPTURE', 'MANUAL_SQLTUNE'or 'AUTO-SQLTUNE' (case insensitive) |
enabled |
Must be ‘YES’ or ‘NO’ (case insensitive) |
accepted |
Must be ‘YES’ or ‘NO’ (case insensitive) |
fixed |
Must be ‘YES’ or ‘NO’ (case insensitive) |
module |
Module (case sensitive) |
action |
Action (case sensitive) |
Return Values
Number of SQL plan baselines packed
RESET_EVOLVE_TASK Procedure
This procedure resets an evolve task to its initial state.
All intermediate results will be removed from the task. Call this procedure on a task that is not currently executing.
Syntax
DBMS_SPM.RESET_EVOLVE_TASK (
task_name IN VARCHAR2);
Parameters
Table 23 RESET_EVOLVE_TASK Procedure Parameters
| Parameter | Description |
|---|---|
task_name |
Identifier of task to reset |
RESUME_EVOLVE_TASK Procedure
The procedure resumes a previously interrupted task.
Syntax
DBMS_SPM.RESUME_EVOLVE_TASK (
task_name IN VARCHAR2);
Parameters
Table 24 RESUME_EVOLVE_TASK Procedure Parameters
| Parameter | Description |
|---|---|
task_name |
Identifier of task to resume |
REPORT_AUTO_EVOLVE_TASK Function
The procedure displays the results of an execution of an automatic evolve task.
Syntax
DBMS_SPM.REPORT_AUTO_EVOLVE_TASK (
type IN VARCHAR2 := TYPE_TEXT,
level IN VARCHAR2 := LEVEL_TYPICAL,
section IN VARCHAR2 := SECTION_ALL,
object_id IN NUMBER := NULL,
execution_name IN VARCHAR2 := NULL)
RETURN CLOB;
Parameters
Table 25 REPORT_AUTO_EVOLVE_TASK Function Parameters
| Parameter | Description |
|---|---|
type |
Type of the report. Possible values are TEXT, HTML, XML |
level |
Format of the report. Possible values are BASIC, TYPICAL, ALL. |
section |
Particular section in the report. Possible values are: SUMMARY, FINDINGS, PLANS, INFORMATION, ERRORS, ALL. |
object_id |
Identifier of the advisor framework object that represents a single plan. If NULL, the report is generated for all objects. |
execution_name |
Name to qualify and identify an execution. If NULL, the report is generated for the last task execution. |
Return Values
The report
REPORT_EVOLVE_TASK Function
The procedure displays the results of an evolved task.
Syntax
DBMS_SPM.REPORT_EVOLVE_TASK (
task_name IN VARCHAR2,
type IN VARCHAR2 := TYPE_TEXT,
level IN VARCHAR2 := LEVEL_TYPICAL,
section IN VARCHAR2 := SECTION_ALL,
object_id IN NUMBER := NULL,
task_owner IN VARCHAR2 := NULL,
execution_name IN VARCHAR2 := NULL)
RETURN CLOB;
Parameters
Table 26 REPORT_EVOLVE_TASK Function Parameters
| Parameter | Description |
|---|---|
task_name |
Identifier of task to report |
type |
Type of the report. Possible values are TEXT, HTML, XML |
level |
Format of the report. Possible values are BASIC, TYPICAL, ALL. |
section |
Particular section in the report. Possible values are: SUMMARY, FINDINGS, PLANS, INFORMATION, ERRORS, ALL. |
object_id |
Identifier of the advisor framework object that represents a single plan. If NULL, the report is generated for all objects. |
task_owner |
Owner of the evolve task. Defaults to the current schema owner. |
execution_name |
Name to qualify and identify an execution. If NULL, the report is generated for the last task execution. |
Return Values
The report
SET_EVOLVE_TASK_PARAMETER Procedure
The procedure sets a parameter of an evolve task, either a VARCHAR2 or a NUMBER.
Syntax
DBMS_SPM.SET_EVOLVE_TASK_PARAMETER (
task_name IN VARCHAR2,
parameter IN VARCHAR2,
value IN NUMBER);
DBMS_SPM.SET_EVOLVE_TASK_PARAMETER (
task_name IN VARCHAR2 := NULL,
parameter IN VARCHAR2,
value IN VARCHAR2);
Parameters
Table 27 SET_EVOLVE_TASK_PARAMETER Procedure Parameters
| Parameter | Description |
|---|---|
task_name |
Evolve task name |
parameter |
Name of the parameter to set (see following table) |
value |
Value of the parameter (see following table) |
The following table describes parameters for the SET_EVOLVE_TASK_PARAMETER procedure.
Table 28 DBMS_SPM.SET_EVOLVE_TASK_PARAMETER Parameters
| Parameter | Description | Default |
|---|---|---|
alternate_plan_source |
Determines which sources to search for additional plans:
You can combine multiple values with the plus sign ( |
The default depends on whether the SPM Evolve Advisor task is automated or manual:
|
alternate_plan_baseline |
Determines which alternative plans should be loaded:
You can combine multiple values with the plus sign ( |
EXISTING |
alternate_plan_limit |
Specifies the maximum number of plans to load in total (that is, not the limit for each SQL statement). | The default depends on whether the SPM Evolve Advisor task is automated or manual:
|
accept_plans |
Specifies whether to accept recommended plans automatically. When When |
true (regardless of whether the advisor is run automatically or manually) |
time_limit |
Global time limit in seconds. This is the total time allowed for the task. | The default depends on whether the SPM Evolve Advisor task is automated or manual:
|
See Also: Oracle AI Database Licensing Information User Manual for details on which features are supported for different editions and services
UNPACK_STGTAB_BASELINE Function
This function unpacks (imports) SQL plan baselines from a staging table into SQL management base.
Syntax
DBMS_SPM.UNPACK_STGTAB_BASELINE (
table_name IN VARCHAR2,
table_owner IN VARCHAR2 := NULL,
sql_handle IN VARCHAR2 := NULL,
plan_name IN VARCHAR2 := NULL,
sql_text IN CLOB := NULL,
creator IN VARCHAR2 := NULL, origin IN VARCHAR2 := NULL,
enabled IN VARCHAR2 := NULL,
accepted IN VARCHAR2 := NULL,
fixed IN VARCHAR2 := NULL,
module IN VARCHAR2 := NULL,
action IN VARCHAR2 := NULL)
RETURN NUMBER;
Parameters
Table 29 UNPACK_STGTAB_BASELINE Function Parameters
| Parameter | Description |
|---|---|
table_name |
Name of staging table from which SQL plan baselines are unpacked (case insensitive unless double quoted) |
table_owner |
Name of staging table owner.Default NULL means current schema is the table owner |
sql_handle |
SQL handle (case sensitive) |
plan_name |
Plan name (case sensitive,% wildcards accepted) |
sql_text |
SQL text string (case sensitive, % wildcards accepted) |
creator |
Creator of SQL plan baseline (case insensitive unless double quoted) |
origin |
Origin of SQL plan baseline, should be 'MANUAL-LOAD', 'AUTO-CAPTURE','MANUAL_SQLTUNE' or 'AUTO-SQLTUNE' (case insensitive) |
enabled |
Must be ‘YES’ or ‘NO’ (case insensitive) |
accepted |
Must be ‘YES’ or ‘NO’ (case insensitive) |
fixed |
Must be ‘YES’ or ‘NO’ (case insensitive) |
module |
Module (case sensitive) |
action |
Action (case sensitive) |
Return Values
Number of plans unpacked