151 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 151-1 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 151-2 DBMS_SPM Package Subprograms

Subprogram Description

ACCEPT_SQL_PLAN_BASELINE Procedure

Accepts a plan based on the recommendation of an evolve task

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_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

IMPLEMENT_EVOLVE_TASK Function

Implements a plan based on the recommendation of an 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 151-3 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.

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 151-4 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

Plan name. It identifies 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 plan attribute to set (see table below).

attribute_value

Value of plan attribute to use (see table below)

Table 151-5 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 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 151-6 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 151-7 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 151-8 Names and Values for CONFIGURE Procedure Parameters

Parameter Name Description Possible Values Default Value

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.

The database only uses this filter when OPTIMIZER_CAPTURE_SQL_PLAN_BASELINES is TRUE.

Action name, for example, R%

  

auto_capture_module

Module to include (=) or exclude (<>) for SQL plan management auto capture, depending on whether allow is TRUE or FALSE. A null value removes the filter for parameter_name entirely.

The database only uses this filter when OPTIMIZER_CAPTURE_SQL_PLAN_BASELINES is TRUE.

Module name, for example, LOGGER

  

auto_capture_parsing_schema_name

Parsing schema to include (=) or exclude (<>) for SQL plan management auto capture, depending on whether allow is TRUE or FALSE. A null value removes the filter for parameter_name entirely.

The database only uses this filter when OPTIMIZER_CAPTURE_SQL_PLAN_BASELINES is TRUE.

Schema name, for example, HR

  

auto_capture_sql_text

Search pattern to apply to SQL text of LIKE or NOT LIKE, depending on whether allow is TRUE or FALSE. A null value removes the filter for parameter_name entirely.

The database only uses this filter when OPTIMIZER_CAPTURE_SQL_PLAN_BASELINES is TRUE.

Text of a SQL statement, for example, SELECT a%

  

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 allow is ignored.

5–523

53

space_budget_percent

Maximum percent of SYSAUX space that can be used for SQL management base.

The database issues alerts when this amount is exceeded. A null value resets the percentage to the default value of 10%. The value of allow is ignored.

1–50

10

Exceptions

Table 151-9 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_name is auto_capture_sql_text, the parameter_value is an automatic search filter. The filter uses the search pattern of LIKE parameter_name when allow=>true. The filter uses the pattern NOT LIKE parameter_name when allow=>false.

    For all other non-null parameter_name values, the search pattern depends on the allow setting. The parameter uses an equal sign (=) when allow=>true. The parameter uses a not-equal sign (<>) when allow=>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_text to be '%TABLE1%', TRUE, and '%TABLE2%', FALSE will result in matching SQL text LIKE '%TABLE1%' and NOT LIKE '%TABLE2%'. The database uses these configuration settings only when the initialization parameter OPTIMIZER_CAPTURE_SQL_PLAN_BASELINES is set to TRUE.

  • A null value for parameter_value removes the filter for parameter_name entirely. By using paramter_value=>'%' in combination with allow=FALSE, you can filter out all values for a parameter, and then create a separate filter to include only specified values. The DBA_SQL_MANAGEMENT_CONFIG view shows the current filters.

  • The default space budget for SQL management base is no more than ten percent of the size of SYSAUX tablespace. 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 151-10 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 151-11 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. Default NULL means current schema is the table owner.

tablespace_name

Name of tablespace. Default NULL means create 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/DBA has to perform a series of steps as follows:

  1. Create a staging table in the source system

  2. Select SQL plan baselines in the source system and pack them into the staging table

  3. Export staging table into a flat file using Oracle EXP utility or Data Pump

  4. Transfer flat file to the target system

  5. Import staging table from the flat file using Oracle IMP utility or Data Pump

  6. 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 151-12 DROP_EVOLVE_TASK Procedure Parameters

Parameter Description

task_name

Identifier of task to drop

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 151-13 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 151-14 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 = 'YES'. The time limit is global and it is used as follows: The time limit for first non-accepted plan verification is set equal to the input value; the time limit for second non-accepted plan verification is set equal to (input value - time spent in first plan verification); and so on.

  • DBMS_SPM.AUTO_LIMIT (Default) lets the system choose an appropriate time limit based on the number of plan verifications required to be done.

  • DBMS_SPM.NO_LIMIT means there is no time limit.

  • A positive integer value represents a user specified time limit.

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.

  • 'YES' (Default) - verifies that a non-accepted plan gives better performance before changing it to an accepted plan

  • 'NO' - directs not to execute plans but only to change non-accepted plans into accepted plans

commit

Specifies whether to update the ACCEPTED status of non-accepted plans from 'NO' to 'YES'.

  • 'YES' (Default) - perform updates of qualifying non-accepted plans and generate a report that shows the updates and the result of performance verification when verify = 'YES'.

  • 'NO' - generate a report without any updates. Note that commit = 'NO' together with verify = 'NO' represents a no-op.

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 151-15 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

IMPLEMENT_EVOLVE_TASK Function

The function implements all the actions recommended by an evolve task.

Syntax

DBMS_SPM.IMPLEMENT_EVOLVE_TASK  (
   task_name       IN  VARCHAR2,
   task_owner      IN  VARCHAR2  := NULL,
   execution_name  IN  VARCHAR2  := NULL,
   force           IN BOOLEAN    := FALSE)
 RETURN NUMBER;

Parameters

Table 151-16 IMPLEMENT_EVOLVE_TASK Function Parameters

Parameter Description

task_name

Identifier of task to report

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 action will be taken for the last task execution.

force

Accept all plans 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.

Return Values

The number of plans accepted

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 151-17 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 151-18 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. NULL means all plans in AWR are selected.

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

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 151-19 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:

  • SQL_TEXT''

  • 'PARSING_SCHEMA_NAME'

  • 'MODULE'

  • 'ACTION'

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 151-20 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 151-21 MIGRATE_STORED_OUTLINE Function Parameters

Parameter Description

attribute_name

Specifies the type of parameter used in attribute_value to identify the migrated stored outlines. It is case insensitive. Possible values:

  • outline_name

  • sql_text

  • category

  • all

attribute_value

Based on attribute_name, this can be:

  • Name of stored outline to be migrated

  • SQL text of stored outlines to be migrated

  • Category of stored outlines to be migrated

  • NULL if attribute_name is all

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 151-22 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 151-23 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 151-24 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 151-25 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 151-26 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 151-27 SET_EVOLVE_TASK_PARAMETER Procedure Parameters

Parameter Description

task_name

Evolve task name

parameter

Name of the parameter to set

value

New value of the parameter

For parameter of type VARCHAR2, the possible parameters are:

  • FIND_NEW_PLANS : Find new plans and verify them (default 'NO'). When this parameter is 'YES', the task will try to find new plans that are not in the plan history and verify them.

  • ALTERNATE_PLAN_SOURCE : Determines which sources to search for alternate plans: ‘CURSOR_CACHE’, ‘AUTOMATIC_WORKLOAD_REPOSITORY’, or ‘SQL_TUNING_SETS’. Multiple values can be combined by delimiting with ‘+’. The default value is ‘CURSOR_CACHE+AUTOMATIC_WORKLOAD_REPOSITORY’.

  • ALTERNATE_PLAN_BASELINE: Value 'EXISTING' indicates that alternate plans should be loaded for statements with existing SQL plan baselines. Value 'NEW' indicates that alternate plans should be loaded for statements which do not have a SQL plan baseline, in which case a new baseline for the statement will be created. Value 'EXISTING+NEW' will load alternate plans in both cases.

For parameter of type NUMBER, the possible parameters are:

  • TIME_LIMIT : Global time limit (default DBMS_SPM.AUTO_LIMIT) in minutes. This is the total time allowed for the task.

  • ALTERNATE_PLAN_LIMIT : The maximum number of alternate plans to load. Default value is 0.

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 151-28 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