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The OPTIMIZER_USE_PLAN_BASELINES parameter is set to TRUE. The optimizer generates a plan for a SQL statement but does not find a matching plan in the SQL plan baseline.<br /> Which two operations are performed by the optimizer in this scenario?（）

A、The optimizer adds the new plan to the plan history.

B、The optimizer selects the new plan for the execution of the SQL statement.

C、The optimizer adds the new plan to the SQL plan baseline as an accepted plan.

D、The optimizer adds the new plan to the SQL plan baseline but not in the ENABLED state.

E、The optimizer costs each of the accepted plans in the SQL plan baseline and picks the one with the lowest cost.

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更多“ The OPTIMIZER_USE_PLAN_BASELINES parameter is set to TRUE. The optimizer generates a plan for a SQL statement but does not find a matching plan in the SQL plan baseline.<br /> Which two operations are performed by the optimizer in this scenario?（）”相关的问题

第1题

[单选题] You perform the following activities during the database upgrade from Oracle Database 10g to Oracle Database 11g: 1. Capture plans for a SQL workload into a SQL Tuning Set (STS) before upgrade. 2. Load these plans from the STS into the SQL plan baseline immediately after the upgrade. What is the reason for performing these activities? （）

A、to minimize plan regression due to the use of a new optimizer version B、to completely avoid the use of new plans generated by a new optimizer version C、to prevent plan capturing when the SQL statement is executed after the database upgrade D、to keep the plan in the plan history so that it can be used when the older version of the optimizer is used

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第2题

[单选题] Your system has been upgraded from Oracle Database 10g to Oracle Database 11g. You imported SQL Tuning Sets (STS) from the previous version. After changing the OPTIMIZER_FEATURE_ENABLE parameter to 10.2.0.4 and running the SQL Performance Analyzer, you observed performance regression for a few SQL statements. What would you do with these SQL statements?（）

A、Set OPTIMIZER_USE_PLAN_BASELINES to FALSE to prevent the use of regressed plans. B、Capture the plans from the previous version using STS and then load them into the stored outline. C、Capture the plans from the previous version using STS and then load them into SQL Management Base (SMB). D、Set OPTIMIZER_CAPTURE_SQL_PLAN_BASELINES to FALSE to prevent the plans from being loaded to the SQL plan baseline.

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第3题

[] The following parameter are set for your Oracle 12c database instance: OPTIMIZER_CAPTURE_SQL_PLAN_BASELINES=FALSE OPTIMIZER_USE_SQL_PLAN_BASELINES=TRUE You want to manage the SQL plan evolution task manually. Examine the following steps: 1. Set the evolve task parameters. 2. Create the evolve task by using the DBMS_SPM.CREATE_EVOLVE_TASK function. 3. Implement the recommendations in the task by using the DBMS_SPM.IMPLEMENT_EVOLVE_TASK function. 4. Execute the evolve task by using the DBMS_SPM.EXECUTE_EVOLVE_TASK function. 5. Report the task outcome by using the DBMS_SPM.REPORT_EVOLVE_TASK function. Identify the correct sequence of steps:（） The following parameter are set for your Oracle 12c database instance: OPTIMIZER_CAPTURE_SQL_PLAN_BASELINES=FALSE OPTIMIZER_USE_SQL_PLAN_BASELINES=TRUE You want to manage the SQL plan evolution task manually. Examine the following steps: 1. Set the evolve task para

A、A.2，4，5 B、B.2，1，4，3，5 C、C.1，2，3，4，5 D、D.1，2，4，5

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第4题

[单选题] View the Exhibit exhibit1 to examine the series of SQL commands. View the Exhibit exhibit2 to examine the plans available in the SQL plan baseline. The baseline in the first row of the Exhibit is created when OPTIMIZER_MODE was set to FIRST_ROWS. Which statement is true if the SQL query in exhibit1 is executed again when the valueof OPTIMIZER_MODE is set to FIRST_ROWS?（）

A、The optimizer uses a new plan because none of the plans in the exhibit2 are fixed plans. B、The optimizer uses the plan in the second row of the exhibit2 because it is an accepted plan. C、The optimizer uses the plan in the first row of the exhibit2 because it is the latest generated plan. D、The optimizer uses the plan in the first row of the exhibit2 because OPTIMIZER_MODE was set to FIRST_ROW during its creation.

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第5题

[单选题] Examine the parameter for your database instance: You generated the execution plan for the following query in the plan table and noticed that the nested loop join was done. After actual execution of the query, you notice that the hash join was done in the execution plan: Identify the reason why the optimizer chose different execution plans.（）

A、The optimizer used a dynamic plan for the query. B、The optimizer chose different plans because automatic dynamic sampling was enabled. C、The optimizer used re-optimization cardinality feedback for the query. D、The optimizer chose different plan because extended statistics were created for the columns used.

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第6题

[多选题] On your Oracle Database, you issue the following commands to create indexes: SQL > CREATE INDEX oe.ord_customer_ix1 ON oe.orders (customer_id, sales_rep_id) INVISIBLE; SQL> CREATE BITMAP INDEX oe.ord_customer_ix2 ON oe.orders (customer_id, sales_rep_id); Which two statements are true?（）

A、Only the ORD_CUSTOMER_IX1 index created. B、Both the indexes are updated when a row is inserted, updated, or deleted in the ORDERS table. C、Both the indexes are created: however, only ORD_CUSTOMERS_IX1 is used by the optimizer for queries on the ORDERS table. D、The ORD_CUSTOMER_IX1 index is not used by the optimizer even when the OPTIMIZER_USE_INVISIBLE_INDEXES parameters is set to true. E、Both the indexes are created and used by the optimizer for queries on the ORDERS table. F、Both the indexes are created: however, only ORD_CUSTOMERS_IX2 is used by the optimizer for queries on the ORDERS table.

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第7题

[] Examine the parameters for your database instance: Which three statements are true about the process of automatic optimization by using cardinality feedback?（） Examine the parameters for your database instance: Which three statements are true about the process of automatic optimization by using cardinality feedback?（）

A、A. The optimizer automatically changes a plan during subsequent execution of a SQL statement if there is a huge difference in optimizer estimates and execution statistics. B、B. The optimizer can re optimize a query only once using cardinality feedback. C、C. The optimizer enables monitoring for cardinality feedback after the first execution of a query. D、D. The optimizer does not monitor cardinality feedback if dynamic sampling and multicolumn statistics are enabled. E、E. After the optimizer identifies a query as a re-optimization candidate, statistics collected by thecollectors are submitted to the optimizer.

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第8题

[单选题] View the Exhibit for some of the parameter settings. You start a session and issue the following command: SQL>CREATE INDEX emp_ename ON emp(ename) TABLESPACE users INVISIBLE; What is the outcome of the above command?（）

A、The index is not used by the optimizer but is maintained during DML operations. B、The index is not used by the optimizer and is not maintained during DML operations. C、The index is used by the optimizer only if a hint is specified in the query statement and is maintained during DML operations. D、The index is used by the optimizer only if a hint is specified in the query statement but is not maintained during DML operations.

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第9题

[] You executed the following commands: Which statement is correct regarding the above statistics collection on the SH.CUSTOMERS table in the above session?（） You executed the following commands: Which statement is correct regarding the above statistics collection on the SH.CUSTOMERS table in the above session?（）

A、A. The statistics are stored in the pending statistics table in the data dictionary. B、B. The statistics are treated as the current statistics by the optimizer for all sessions. C、C. The statistics are treated as the current statistics by the optimizer for the current sessions only. D、D. The statistics are temporary and used by the optimizer for all sessions until this session terminates.

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