单选题As a result of performance analysis， you created an index on the prod_name column of the prod_det table， which contains about ten thousand rows. Later， you updated a product name in the table. How does this change affect the index？（）A A leaf will be ma

题目
单选题
As a result of performance analysis， you created an index on the prod_name column of the prod_det table， which contains about ten thousand rows. Later， you updated a product name in the table. How does this change affect the index？（）
A

A leaf will be marked as invalid.

B

An update in a leaf row takes place.

C

The index will be updated automatically at commit.

D

A leaf row in the index will be deleted and inserted.

E

The index becomes invalid when you make any updates.

相似考题

1.An index called ORD_CUSTNAME_IX has been created on the CUSTNAME column in the ORDERS table using the following command:SQL>CREATE INDEX ord_custname_ix ON orders(custname);The ORDERS table is frequently queried using the CUSTNAME column in the WHERE clause.You want to check the impact on the performance of the queries if the index is not available. You do not want the index to be dropped or rebuilt to perform this test.Which is the most efficient method of performing this task?（）A. disabling the indexB. making the index invisibleC. making the index unusableD. using the MONITORING USAGE clause for the index

2. You work in a company which uses SQL Server 2008. You are the administrator of the company database. Now you are in charge of a SQL Server 2008 instance. There is a database named named Dworks in the instance. The Dworks table has a table named BillDetails which has a clustered primary key named BillId on the BillId column. The BillDetails table has a single XML column named GoodsDetails. The XML column has an XML index and XML data are stored in this XML column. A new column named GoodsID is added to the BillDetails table. GoodsID must be included in the primary key.  So what action should you perform to achieve this goal？（）  A、You should drop the XML index on the table. Modify the primary key. Recreate the XML index B、You should alter the XML index and set the ALLOW_ROW_LOCKS = OFF option. Alter the primary key and set the ALLOW_ROW_LOCKS = ON option. C、You should move the XML data to a temporary table. Clear the XML data from the original table by setting the GoodsDetails column to NULL. Modify the primary key. Repopulate the ProductSpecs column. D、You should disable the XML index on the GoodsDetails column. Modify the primary key.Enable the XML index on the ProductSpecs column.

3. In your test database， you have created the ORDERS table as an index/x7forganized table （IOT）. To facilitate faster querying， you have created a mapping table and a bitmap index on the ORDER_FILLED column. You observe that the query performance degrades when users perform a large volume of transactions.  While investigating the reason， you find that the mapping table segment is fragmented， leading to poor performance. Which option would you use to defragment the mapping table without affecting the original table data？（）A、export and import the mapping tableB、drop and re­create the mapping tableC、truncate the mapping table and reinsert the valuesD、use the ALTER TABLE .. REBUILD command to defragment the mapping table

4.You have altered a non-unique index to be invisible to determine if queries execute within an acceptable response time without using this index.Which two are possible if table updates are performed which affect the invisible index columns?（）A. The index remains invisible.B. The index is not updated by the DML statements on the indexed table.C. The index automatically becomes visible in order to have it updated by DML on the table.D. The index becomes unusable but the table is updated by the DML.E. The index is updated by the DML on the table.

更多“单选题As a result of performance analysis， you created an index on the prod_name column of the prod_det table， which contains about ten thousand rows. Later， you updated a product name in the table. How does this change affect the index？（）A A leaf will be ma”相关问题

  • 第1题：

    An index called ORD_CUSTNAME_IX has been created on the CUSTNAME column in the ORDERS table using the following command：   SQL>CREATE INDEX ord_custname_ix ON orders（custname）；   The ORDERS table is frequently queried using the CUSTNAME column in the WHERE clause. You want to check the impact on the performance of the queries if the index is not available. You do not want the index to be dropped or rebuilt to perform this test.  Which is the most efficient method of performing this task？（）

    • A、 disabling the index
    • B、 making the index invisible
    • C、 making the index unusable
    • D、 using the MONITORING USAGE clause for the index

    正确答案:B

  • 第2题：

    The ST_INFO master table has millions of rows that are updated very rarely. It has a STATE_CODE column that contains the value for 25 states. The table is frequently queried on the STATE_CODE column. Which type of index would you suggest to improve the query performance？（）

    • A、B-tree
    • B、bitmap
    • C、reverse key
    • D、function based

    正确答案:B

  • 第3题：

    You need to change the definition of an existing table. The COMMERCIALS table needs its DESCRIPTION column changed to hold varying length characters up to 2000 bytes. The column can currently hold 1000 bytes per value. The table contains 20000 rows. Which statement is valid?（）

    • A、ALTER TABLE commercials MODIFY (description CHAR2(2000));
    • B、ALTER TABLE commercials CHANGE (description CHAR2(2000));
    • C、ALTER TABLE commercials CHANGE (description VARCHAR2 (2000));
    • D、ALTER TABLE commercials MODIFY (description VARCHAR2 (2000));
    • E、You cannot increase the size of a column if the table has rows.

    正确答案:D

  • 第4题：

    You have created an Oracle 10g database named SALES， which will be used by an application named SalesOrders. Users of the SalesOrders application complain that application response time is slow when they generate reports. The SalesOrders application accesses a table that contains 10 million rows. You decide to create an index on this table using the NOLOGGING option so that the index creation process is completed in the least amount of time. Which of the following is NOT true about an index created with the NOLOGGING option？（）

    • A、 The index can be changed from NOLOGGING to LOGGING
    • B、 The index cannot be recovered even in the ARCHIVELOG mode.
    • C、 The index can only be created if the base table is created with the NOLOGGING option.
    • D、 The index can be recovered if you perform a backup after the CREATE INDEX statement.

    正确答案:C

  • 第5题：

    The SCOTT user has an index on the ITEM_DESC column of the ITEM table. As part of the year-ending task， SCOTT updates the ITEM_DESC column for most of the rows in the ITEM table. How does this change to the table affect the index？（）

    • A、An update in a leaf row takes place.
    • B、The index becomes invalid after the update.
    • C、The leaf block containing the row to be updated is marked as invalid.
    • D、A row in the leaf block of the index for the key value is deleted and inserted.

    正确答案:D

  • 第6题：

    You are modifying a table named Product in a SQL Server 2005 database. You want to add a new column named FriendlyName to the Product table. A friendly name for each product will be stored in this column. The table currently contains data. The sales department has not yet created a friendly name for each product. FriendlyName is a required value for each product. You want to add this new column by using the least amount of effort. What should you do？（）

    • A、Define the new column as NULL.Update the FriendlyName column to the same value as the productName column. Alter the FriendlyName column to be NOT NULL.
    • B、Define the new column as NOT NULL with a default value of ’Undefined.’
    • C、Define the new column as NULL. Use application logic to enforce the data constraint.
    • D、Define the new column as NULL with a default value of ’Undefined.’

    正确答案:B

  • 第7题：

    单选题
    You work as a database administrator for Certkiller .com. As a result of performance analysis， you created an index on theprod_namecolumn of the  Certkiller prodtable， which contains about ten thousand rows. Later， you updated a product name in the table.  How does this change affect the index？（）
    A

    A leaf will be marked as invalid.

    B

    An update in a leaf row takes place.

    C

    The index will be updated automatically at commit.

    D

    A leaf row in the index will be deleted and inserted.

    E

    The index becomes invalid when you make any updates


    正确答案： D
    解析： 暂无解析

  • 第8题：

    单选题
    You are using Oracle Enterprise Manager to estimate the size of a table to be created. You have typed data regarding the column names， data types， sizes of the columns， and the projected number of rows in the table. Which additional information does the Oracle Enterprise Manager return？（）
    A

     space allocated in the tablespace

    B

     space required for the bitmap index on a column of the table

    C

     space remaining in the tablespace after creating the table

    D

     estimated value of the PCTFREE storage parameter


    正确答案： C
    解析： 暂无解析

  • 第9题：

    单选题
    The SCOTT user has an index on the ITEM_DESC column of the ITEM table. As part of the year-ending task， SCOTT updates the ITEM_DESC column for most of the rows in the ITEM table. How does this change to the table affect the index？（）
    A

    An update in a leaf row takes place.

    B

    The index becomes invalid after the update.

    C

    The leaf block containing the row to be updated is marked as invalid.

    D

    A row in the leaf block of the index for the key value is deleted and inserted.


    正确答案： B
    解析： 暂无解析

  • 第10题：

    单选题
    The ST_INFO master table has millions of rows that are updated very rarely. It has a STATE_CODE column that contains the value for 25 states. The table is frequently queried on the STATE_CODE column.  Which type of index would you suggest to improve the query performance？（）
    A

    B­tree

    B

    bitmap

    C

    reverse key

    D

    function based


    正确答案： C
    解析： 暂无解析

  • 第11题：

    单选题
    You have created an Oracle 10g database named SALES， which will be used by an application named SalesOrders. Users of the SalesOrders application complain that application response time is slow when they generate reports. The SalesOrders application accesses a table that contains 10 million rows. You decide to create an index on this table using the NOLOGGING option so that the index creation process is completed in the least amount of time. Which of the following is NOT true about an index created with the NOLOGGING option？（）
    A

     The index can be changed from NOLOGGING to LOGGING

    B

     The index cannot be recovered even in the ARCHIVELOG mode.

    C

     The index can only be created if the base table is created with the NOLOGGING option.

    D

     The index can be recovered if you perform a backup after the CREATE INDEX statement.


    正确答案： D
    解析： 暂无解析

  • 第12题：

    单选题
    You work in a company which is named Wiikigo Corp. The company uses SQL Server 2008. You are the administrator of the company database. Now you are in charge of a SQL Server 2008 instance. There is a database which is named Sellings in the instance. The Sellings database contains a table named Productions. The table is used to stores information about all types of products. The Productions table is often queried by users on the basis of the RadioSize column. The RadioSize column contains the NULL value for all products other than Radios. Currently no index exists on the RadionSize column. According to the requirement of the company CIO, you have to optimize the query performance and reduce the effect on the disk space to the least. So what action should you perform to achieve this goal?（）
    A

    On the Products table, you should create a view. 

    B

    On the RadioSize column, you should create a clustered index 

    C

    On the RadioSize column, you should create a filtered index 

    D

    On the RadioSize column, you should create a unique clustered index


    正确答案： A
    解析： 暂无解析

  • 第13题：

    As a result of performance analysis， you created an index on the prod_name column of the prod_det table， which contains about ten thousand rows. Later， you updated a product name in the table. How does this change affect the index？（）

    • A、A leaf will be marked as invalid.
    • B、An update in a leaf row takes place.
    • C、The index will be updated automatically at commit.
    • D、A leaf row in the index will be deleted and inserted.
    • E、The index becomes invalid when you make any updates.

    正确答案:D

  • 第14题：

    Which statement describes the effect on an index， when the indexed column for the rows is updatedin the base table（）

    • A、An update in a leaf row takes place.
    • B、The index becomes invalid after the update.
    • C、The leaf block containing the row to be updated is marked as invalid.
    • D、A row in the leaf block of the index for the key value is logically deleted and a new leaf row is inserted

    正确答案:D

  • 第15题：

    You work as a database administrator for Certkiller .com. As a result of performance analysis， you created an index on theprod_namecolumn of the  Certkiller prodtable， which contains about ten thousand rows. Later， you updated a product name in the table.  How does this change affect the index？（）

    • A、A leaf will be marked as invalid.
    • B、An update in a leaf row takes place.
    • C、The index will be updated automatically at commit.
    • D、A leaf row in the index will be deleted and inserted.
    • E、The index becomes invalid when you make any updates

    正确答案:D

  • 第16题：

    You are using Oracle Enterprise Manager to estimate the size of a table to be created. You have typed data regarding the column names， data types， sizes of the columns， and the projected number of rows in the table. Which additional information does the Oracle Enterprise Manager return？（）

    • A、 space allocated in the tablespace
    • B、 space required for the bitmap index on a column of the table
    • C、 space remaining in the tablespace after creating the table
    • D、 estimated value of the PCTFREE storage parameter

    正确答案:A

  • 第17题：

    You have altered a non-unique index to be invisible to determine if queries execute within an acceptable response time without using this index. Which two are possible if table updates are performed which affect the invisible index columns?（）

    • A、The index remains invisible.
    • B、The index is not updated by the DML statements on the indexed table.
    • C、The index automatically becomes visible in order to have it updated by DML on the table.
    • D、The index becomes unusable but the table is updated by the DML.
    • E、The index is updated by the DML on the table.

    正确答案:A,E

  • 第18题：

    You work in a company which is named Wiikigo Corp. The company uses SQL Server 2008. You are the administrator of the company database. Now you are in charge of a SQL Server 2008 instance. There is a database which is named Sellings in the instance. The Sellings database contains a table named Productions. The table is used to stores information about all types of products. The Productions table is often queried by users on the basis of the RadioSize column. The RadioSize column contains the NULL value for all products other than Radios. Currently no index exists on the RadionSize column. According to the requirement of the company CIO, you have to optimize the query performance and reduce the effect on the disk space to the least. So what action should you perform to achieve this goal?（）  

    • A、On the Products table, you should create a view. 
    • B、On the RadioSize column, you should create a clustered index 
    • C、On the RadioSize column, you should create a filtered index 
    • D、On the RadioSize column, you should create a unique clustered index

    正确答案:C

  • 第19题：

    单选题
    In your test database， you have created the ORDERS table as an index-organized table （IOT）. To facilitate faster querying， you have created a mapping table and a bitmap index on the ORDER_FILLED column. You observe that the query performance degrades when users perform a large volume of transactions.  While investigating the reason， you find that the mapping table segment is fragmented， leading to poor performance.   Which option would you use to defragment the mapping table without affecting the original table data？（）
    A

    export and import the mapping table

    B

    drop and re-create the mapping table

    C

    truncate the mapping table and reinsert the values

    D

    use the ALTER TABLE···REBUILD command to defragment the mapping table


    正确答案： B
    解析： 暂无解析

  • 第20题：

    单选题
    An index called ORD_CUSTNAME_IX has been created on the CUSTNAME column in the ORDERS table using the following command：   SQL>CREATE INDEX ord_custname_ix ON orders（custname）；   The ORDERS table is frequently queried using the CUSTNAME column in the WHERE clause. You want to check the impact on the performance of the queries if the index is not available. You do not want the index to be dropped or rebuilt to perform this test.  Which is the most efficient method of performing this task？（）
    A

     disabling the index

    B

     making the index invisible

    C

     making the index unusable

    D

     using the MONITORING USAGE clause for the index


    正确答案： D
    解析： 暂无解析

  • 第21题：

    单选题
    In your test database， you have created the ORDERS table as an index-organized table （IOT）. To facilitate faster querying， you have created a mapping table and a bitmap index on the ORDER_FILLED column. You observe that the query performance degrees when users perform a large volume of transactions. While investigating the reason， you find that the mapping table segment is fragmented， leading to poor performance. Which option would you use to defragment the mapping table without affecting the original table data？（）
    A

     Export and import the mapping table.

    B

     Drop and re-create the mapping table.

    C

     Truncate the mapping table and reinsert the values.

    D

     Use the ALTER TABLE .. REBUILD command to defragment the mapping table.


    正确答案： B
    解析： 暂无解析

  • 第22题：

    单选题
    You are modifying a table named Product in a SQL Server 2005 database. You want to add a new column named FriendlyName to the Product table. A friendly name for each product will be stored in this column. The table currently contains data. The sales department has not yet created a friendly name for each product. FriendlyName is a required value for each product. You want to add this new column by using the least amount of effort. What should you do？（）
    A

    Define the new column as NULL.Update the FriendlyName column to the same value as the productName column. Alter the FriendlyName column to be NOT NULL.

    B

    Define the new column as NOT NULL with a default value of ’Undefined.’

    C

    Define the new column as NULL. Use application logic to enforce the data constraint.

    D

    Define the new column as NULL with a default value of ’Undefined.’


    正确答案： D
    解析： 暂无解析

  • 第23题：

    单选题
    An index called ORD_CUSTNAME_IX has been created on the CUSTNAME column in the ORDERS table using the following command: SQL>CREATE INDEX ord_custname_ix ON orders(custname); The ORDERS table is frequently queried using the CUSTNAME column in the WHERE clause. You want to check the impact on the performance of the queries if the index is not available. You do not want the index to be dropped or rebuilt to perform this test.Which is the most efficient method of performing this task?（）
    A

    disabling the index

    B

    making the index invisible

    C

    making the index unusable

    D

    using the MONITORING USAGE clause for the index


    正确答案： D
    解析： 暂无解析

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