单选题Which object may be used during query optimization to improve the performance for a subset of SELECT queries?（）A MQTB TriggerC Read Only CursorD Stored Procedure

题目
单选题
Which object may be used during query optimization to improve the performance for a subset of SELECT queries?（）
A

MQT

B

Trigger

C

Read Only Cursor

D

Stored Procedure

相似考题

1.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.

2.Which statement is TRUE concerning buoyant work vests aboard tankers ________．A.They may be worn while working on deck but not while working over the sideB.They must be used only under supervision of a designated ship's officerC.They will be accepted for up to 10% of the required life preserversD.They may be worn during drills

3.Which statements concerning the value of a member variable are true， when no explicit assignments have been made？（）  A、The value of an int is undetermined.B、The value of all numeric types is zero.C、The compiler may issue an error if the variable is used before it is initialized.D、The value of a String variable is "" （empty string）.E、The value of all object variables is null.

4.A query is used to search through the database to locate a particular record or records, which conform. to specified (75) .A．criteriaB．standardsC．methodsD．conditions

更多“Which object may be used during query optimization to improv”相关问题

  • 第1题：

    Which of the following statements best describes Flashback Versions Query？（）  

    • A、 Flashback Versions Query is used to make changes to multiple versions of data that existed between two points in time.
    • B、 Flashback Versions Query is used to view all version changes on rows that existed between the time  the query was executed and a point in time in the past.
    • C、 Flashback Versions Query is used to view version changes and the SQL to undo those changes on rows that existed between two points in time.
    • D、 Flashback Versions Query is used to view all version changes on rows that existed between two  points in time.

    正确答案:D

  • 第2题：

    Which command can be used to display information from the PvDv object class in the ODM？（）  

    • A、odmlist
    • B、odmshow
    • C、lsdev -P
    • D、lsattr -El

    正确答案:C

  • 第3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.

    正确答案:B

  • 第4题：

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

    • 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、The optimizer can re optimize a query only once using cardinality feedback.
    • C、The optimizer enables monitoring for cardinality feedback after the first execution of a query.
    • D、The optimizer does not monitor cardinality feedback if dynamic sampling and multicolumn statistics are enabled.
    • E、After the optimizer identifies a query as a re-optimization candidate, statistics collected by the collectors are submitted to the optimizer.

    正确答案:A,C,D

  • 第5题：

    单选题
    When does Oracle9i flag an index as being used in the V$OBJECT_USAGE view？（）
    A

    During a query’s parse time only. 

    B

    During a query’s execution time only. 

    C

    During any kind of DML statement execution. 

    D

    During the execution of an INSERT statement only.


    正确答案： A
    解析： 暂无解析

  • 第6题：

    单选题
    The operation of which aids to navigation may be suspended during war or national emergency（）.
    A

    Navigational satellites

    B

    Loran

    C

    Omega

    D

    Any of the above


    正确答案： C
    解析： 暂无解析

  • 第7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.


    正确答案： A
    解析： 暂无解析

  • 第8题：

    单选题
    You have many users complaining about slow inserts into a large table. While investigating the reason， you find that the number of indexes on the table is high. You want to find out which indexes are not being used.  Which method would you follow to achieve this？（）
    A

    enable index monitoring and query the DBA_OBJECTS view

    B

    enable index monitoring and query the DBA_INDEXES view

    C

    enable index monitoring and query the V$OBJECT_USAGE view

    D

    enable index monitoring and view the DBA_INDEXTYPE_COMMENTS view


    正确答案： A
    解析： 暂无解析

  • 第9题：

    单选题
    Which object may be used during query optimization to improve the performance for a subset of SELECT queries?（）
    A

    MQT

    B

    Trigger

    C

    Read Only Cursor

    D

    Stored Procedure


    正确答案： D
    解析： 暂无解析

  • 第10题：

    单选题
    Which of the following statements is true regarding the VERSIONS BETWEEN clause？（）
    A

     The VERSIONS BETWEEN clause may be used in DML statements.

    B

     The VERSIONS BETWEEN clause may be used in DDL statements.

    C

     The VERSIONS BETWEEN clause may not be used to query past DDL changes to tables.

    D

     The VERSIONS BETWEEN clause may not be used to query past DML statements to tables.


    正确答案： A
    解析： 暂无解析

  • 第11题：

    单选题
    When the engine room is put in standby condition, the engineer in charge of the watch need not to（）
    A

    ensure all machinery which may be used during maneuvering is in ready

    B

    ensure an adequate reserve of power is available for steering gear and other requirements

    C

    keep the main propulsion unit controls continuously attended when in the manual mode of operation

    D

    ensure all machinery which may be used during maneuvering is running stably


    正确答案： D
    解析： 暂无解析

  • 第12题：

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

    The optimizer can re optimize a query only once using cardinality feedback.

    C

    The optimizer enables monitoring for cardinality feedback after the first execution of a query.

    D

    The optimizer does not monitor cardinality feedback if dynamic sampling and multicolumn statistics are enabled.

    E

    After the optimizer identifies a query as a re-optimization candidate, statistics collected by the collectors are submitted to the optimizer.


    正确答案： C,B
    解析： 暂无解析

  • 第13题：

    Which of the following statements is true regarding the VERSIONS BETWEEN clause？（）  

    • A、 The VERSIONS BETWEEN clause may be used in DML statements.
    • B、 The VERSIONS BETWEEN clause may be used in DDL statements.
    • C、 The VERSIONS BETWEEN clause may not be used to query past DDL changes to tables.
    • D、 The VERSIONS BETWEEN clause may not be used to query past DML statements to tables.

    正确答案:C

  • 第14题：

    Which statement is true about the database and database-user used during installation of IMS Server？（）

    • A、A preexisting database user may be used but a new database has to be created during installation.
    • B、A preexisting database may be used but a new database user has to be created during installation.
    • C、A preexisting database and user may be used or a new database and user are created during installation.
    • D、A preexisting database and user cannot be used； a new database and user are created during  installation.

    正确答案:C

  • 第15题：

    Which two statements are true about WHERE and HAVING clauses? （）

    • A、A WHERE clause can be used to restrict both rows and groups.
    • B、A WHERE clause can be used to restrict rows only.
    • C、A HAVING clause can be used to restrict both rows and groups.
    • D、A HAVING clause can be used to restrict groups only.
    • E、A WHERE clause CANNOT be used in a query if the query uses a HAVING clause.
    • F、A HAVING clause CANNOT be used in subqueries.

    正确答案:B,D

  • 第16题：

    Which is an example of a dynamic SELECT statement? （）

    • A、A query whose object names change during its execution. 
    • B、A query whose object names are not known until run time. 
    • C、A query whose bind variables values change during execution. 
    • D、A query whose bind variable values are not known until run time.

    正确答案:B

  • 第17题：

    单选题
    Which of the following statements best describes Flashback Versions Query？（）
    A

     Flashback Versions Query is used to make changes to multiple versions of data that existed between two points in time.

    B

     Flashback Versions Query is used to view all version changes on rows that existed between the time  the query was executed and a point in time in the past.

    C

     Flashback Versions Query is used to view version changes and the SQL to undo those changes on rows that existed between two points in time.

    D

     Flashback Versions Query is used to view all version changes on rows that existed between two  points in time.


    正确答案： A
    解析： 暂无解析

  • 第18题：

    多选题
    Which the two are true about the JSTL core iteration custom tags？（）
    A

    It may iterate over arrays， collections， maps and strings.

    B

    The body of the tag may contain EL code， but not scripting code.

    C

    When looping over collections， a loop status object may be used in the tag body.

    D

    It may iterate over a map， but only the key of the mapping may be used in the tag body.

    E

    When looping over integers （for example begin1=’1’ end=’10’）， a loop status object may not be used in the tag body.


    正确答案： A,C
    解析： 暂无解析

  • 第19题：

    多选题
    Which three functions are performed by the SQL Tuning Advisor？（）
    A

    Building the SQL profile

    B

    Recommending optimization of materialized views

    C

    Checking query objects for missing and stale statistics

    D

    Recommending bitmap， function-based， and B-tree indexes

    E

    Recommending restructuring SQL queries that are using bad plans


    正确答案： C,B
    解析： 暂无解析

  • 第20题：

    单选题
    Which is an example of a dynamic SELECT statement? （）
    A

    A query whose object names change during its execution. 

    B

    A query whose object names are not known until run time. 

    C

    A query whose bind variables values change during execution. 

    D

    A query whose bind variable values are not known until run time.


    正确答案： B
    解析： 暂无解析

  • 第21题：

    单选题
    Which statement is true about the database and database-user used during installation of IMS Server？（）
    A

    A preexisting database user may be used but a new database has to be created during installation.

    B

    A preexisting database may be used but a new database user has to be created during installation.

    C

    A preexisting database and user may be used or a new database and user are created during installation.

    D

    A preexisting database and user cannot be used； a new database and user are created during  installation.


    正确答案： C
    解析： 暂无解析

  • 第22题：

    多选题
    Which two statements are true about WHERE and HAVING clauses? （）
    A

    A WHERE clause can be used to restrict both rows and groups.

    B

    A WHERE clause can be used to restrict rows only.

    C

    A HAVING clause can be used to restrict both rows and groups.

    D

    A HAVING clause can be used to restrict groups only.

    E

    A WHERE clause CANNOT be used in a query of the query uses a HAVING clause.

    F

    A HAVING clause CANNOT be used in subqueries.


    正确答案： E,B
    解析： 暂无解析

  • 第23题：

    单选题
    You find this query being used in your Oracle 12c database: Which method a used by the optimizer to limit the rows being returned?（）
    A

    A filter is added to the table query dynamically using ROWNUM to limit the rows to 20 percent of the total rows

    B

    All the rows are returned to the client or middle tier but only the first 20 percent are returned to the screen or the application.

    C

    A view is created during execution and a filter on the view limits the rows to 20 percent of the total rows.

    D

    A TOP-N query is created to limit the rows to 20 percent of the total rows


    正确答案： B
    解析： 暂无解析

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