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

第1题：

第2题：

In your database，the STATISTICS_LEVEL initialization parameter is set to BASIC. What is the impact of this setting？（）

• A、The optimizer statistics are collected automatically.
• B、Only the timed operating system （OS） statistics and plan execution statistics are collected.
• C、The Oracle server dynamically generates the necessary statistics on tables as part of query optimization.
• D、The snapshots for the Automatic Workload Repository （AWR） are not generated automatically. 
• E、Snapshots cannot be collected manually by using DBMS_WORKLOAD_REPOSITORY PACKAGE.

第3题：

第4题：

You want to analyze a SQL Tuning Set （STS） using SQL Performance Analyzer in a test database. Which two statements are true regarding the activities performed during the test execution of SQLs in a SQL Tuning Set？（）

• A、 Every SQL statement in the STS is considered only once for execution.
• B、 The SQL statements in the STS are executed concurrently to produce the execution plan and execution statistics.
• C、 The execution plan and execution statistics are computed for each SQL statement in the STS. 
• D、 The effects of DDL and DML are considered to produce the execution plan and execution statistics.

第5题：

You are using the Database Resource Manager to manage database resources. You created a resource plan directive for the MANAGERS resource consumer group under the SALES_PLAN by using the following statement：   SQL>EXEC DBMS_RESOURCE_MANAGER.CREATE_PLAN_DIRECTIVE   （PLAN => ’SALES_PLAN’，   GROUP_OR_SUBPLAN => ’MANAGERS’，   CPU_P1 => 100， CPU_P2 =>0，   SWITCH_GROUP => ’CLERKS’，   SWITCH_TIME_IN_CALL => 600）；   A user， SCOTT， who is assigned to the MANAGERS group， starts a database session and executes a query on the database. What is the outcome if the query takes approximately 15 minutes to complete？（）  

• A、 The query starts under the CLERKS group and the user， SCOTT， switches back to the MANAGERS group after the query completes.
• B、 The query starts under the MANAGERS group but terminates with an error when the execution time exceeds 10 minutes.
• C、 The query starts under the MANAGERS group and switches automatically to the CLERKS group when the execution time exceeds 10 minutes. The query does not switch back to the MANAGERS group after the query completes.
• D、 The query starts under the MANAGERS group， the user SCOTT switches automatically to the CLERKS group when the execution time exceeds 10 minutes， and then switches back to the MANAGERS group after the query completes.

第6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.

第7题：

A new report process containing a complex query is written, with high impact on the database. You wantto collect basic statistics about query, such as the level of parallelism, total database time, and the number of I/O requests. For the database instance STATISTICS_LEVEL, the initialization parameter is set to TYPICAL and theCONTROL_MANAGEMENT_PACK_ACCESS parameter is set to DIAGNOSTIC+TUNING. What should you do to accomplish this task?（）

• A、Execute the query and view Active Session History (ASH) for information about the query.
• B、Enable SQL trace for the query.
• C、Create a database operation, execute the query, and use the DBMS_SQL_MONITOR. REPORT_SQL_MONITOR function to view the report.
• D、Use the DBMS_APPLICATION_INFO.SET_SESSION_LONGOPS procedure to monitor query execution and view the information from the V$SESSION_LONGOPS view.

第8题：

第9题：

You execute the following command in your Certkiller .com production database to change the width of the CUST_NAME column of the CUSTOMERS table： ALTER TABLE customers  MODIFY （cust_nameVARCHAR2 （40）） /  When you execute the command， it displays the following error message：  ERROR at line 1：  ORA-00054： resource busy and acquire with NOWAIT specified  What could be the reason for the error message？（）

• A、The database instance is not available.
• B、The ALTER TABLE command does not have WAIT option
• C、The table or a row in the table is currently locked by another user session.
• D、The database instance is busy processing other user sessions commands.
• E、The CUSTOMERS table has no long running query active at the time when this request is made.
• F、The server process executing the ALTER TABLE command is busy with another command execution

第10题：

You execute the following commands to audit database activities: SQL > ALTER SYSTEM SET AUDIT_TRIAL=DB, EXTENDED SCOPE=SPFILE; SQL > AUDIT SELECT TABLE, INSERT TABLE, DELETE TABLE BY JOHN By SESSION WHENEVER SUCCESSFUL; Which statement is true about the audit record that generated when auditing after instance restarts?（）

• A、One audit record is created for every successful execution of a SELECT, INSERT OR DELETE command on a table, and contains the SQL text for the SQL Statements.
• B、One audit record is created for every successful execution of a SELECT, INSERT OR DELETE command, and contains the execution plan for the SQL statements.
• C、One audit record is created for the whole session if john successfully executes a SELECT, INSERT, or DELETE command, and contains the execution plan for the SQL statements.
• D、One audit record is created for the whole session if JOHN successfully executes a select command, and contains the SQL text and bind variables used.
• E、One audit record is created for the whole session if john successfully executes a SELECT, INSERT,or DELETE command on a table, and contains the execution plan, SQL text, and bind variables used.