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.
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.
相关考题：
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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.
While designing your database， you have created the EMPLOYEES table as an index/x7forganized table （IOT）. You want to create a bitmap index on the JOB_ID column to make queries faster. Which task must have been completed so that you are able to create the bitmap index？（）A、A primary key must have been created.B、A mapping table must have been created.C、An overflow tablespace must have been specified.D、The PCTTHRESHOLD option must have been specified.
While designing your database， you have created the EMPLOYEES table as an index-organized table （IOT）. You want to create a bitmap index on the JOB_ID column to make queries faster. Which task must have been completed so that you are able to create the bitmap index？（） A、A primary key must have been created.B、A mapping table must have been created.C、An overflow tablespace must have been specified.D、The PCTTHRESHOLD option must have been specified.
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.
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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
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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 tablespaceB、 space required for the bitmap index on a column of the tableC、 space remaining in the tablespace after creating the tableD、 estimated value of the PCTFREE storage parameter
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.
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.
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.’
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
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？（）AA leaf will be marked as invalid.BAn update in a leaf row takes place.CThe index will be updated automatically at commit.DA leaf row in the index will be deleted and inserted.EThe index becomes invalid when you make any updates
单选题Which statement describes the effect on an index， when the indexed column for the rows is updatedin the base table（）AAn update in a leaf row takes place.BThe index becomes invalid after the update.CThe leaf block containing the row to be updated is marked as invalid.DA row in the leaf block of the index for the key value is logically deleted and a new leaf row is inserted
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 tablespaceB space required for the bitmap index on a column of the tableC space remaining in the tablespace after creating the tableD estimated value of the PCTFREE storage parameter
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？（）AAn update in a leaf row takes place.BThe index becomes invalid after the update.CThe leaf block containing the row to be updated is marked as invalid.DA row in the leaf block of the index for the key value is deleted and inserted.
单选题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？（）AYou should drop the XML index on the table. Modify the primary key. Recreate the XML index BYou 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. CYou 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. DYou should disable the XML index on the GoodsDetails column. Modify the primary key.Enable the XML index on the ProductSpecs column.
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.
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？（）AA leaf will be marked as invalid.BAn update in a leaf row takes place.CThe index will be updated automatically at commit.DA leaf row in the index will be deleted and inserted.EThe index becomes invalid when you make any updates.
单选题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?（）AALTER TABLE commercials MODIFY (description CHAR2(2000));BALTER TABLE commercials CHANGE (description CHAR2(2000));CALTER TABLE commercials CHANGE (description VARCHAR2 (2000));DALTER TABLE commercials MODIFY (description VARCHAR2 (2000));EYou cannot increase the size of a column if the table has rows.