单选题Two database users, Jack and Bill, are accessing the SupportCenter STAFF table of the SupportCenter DB database. When Jack modifies a value in the table, the new value is invisible to Bill. Which is the modified value invisible to Bill?（）A The modified

第1题：

Two database users， Jack and Bill， are accessing the Certkiller STAFF table of the Certkiller DB database. When Jack modifies a value in the table， the new value is invisible to Bill.  Which is the modified value invisible to Bill？（）

• A、The modified data are not available on disk.
• B、The modified data have been flushed out from memory.
• C、The modified rows of the Certkiller STAFF table have been locked.
• D、Jack has not committed the changes after modifying the value.
• E、Both users are accessing the database from two different machines.

第2题：

In which two ways can you influence how downstream LSRs treat MPLS traffic?（）

• A、Use an EXP rewrite table.
• B、Use a DSCP rewrite table.
• C、Statically assign a CoS value to an LDP-signaled LSP.
• D、Statically assign a CoS value to an RSVP-signaled LSP.

第3题：

Identify the two situations in which you use the alert log file in your database to check the details.（）

• A、Running a query on a table returns "ORA-600： Internal Error."
• B、Inserting a value in a table returns "ORA-01722： invalid number."
• C、Creating a table returns "ORA-00955： name is already used by an existing object."
• D、Inserting a value in a table returns "ORA-00001： unique constraint （SYS.PK_TECHP） violated." 
• E、Inserting a row in a table returns "ORA-00060： deadlock detected while waiting for resource."

第4题：

Two database users, Jack and Bill, are accessing the SupportCenter STAFF table of the SupportCenter DB database. When Jack modifies a value in the table, the new value is invisible to Bill. Which is the modified value invisible to Bill?（）

• A、The modified data are not available on disk.
• B、The modified data have been flushed out from memory.
• C、The modified rows of the SupportCenter STAFF table have been locked.
• D、Jack has not committed the changes after modifying the value.
• E、Both users are accessing the database from two different machines.

第5题：

A table was just created on your Oracle database with six extents allocated to it. Which of the following factors most likely caused the table to have so many extents allocated?（）

• A、The value for MINEXTENTS setting 
• B、The value for PCTINCREASE setting 
• C、The value for MAXEXTENTS setting 
• D、By default, Oracle allocates six extents to all database objects

第6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.

第7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.’

第8题：

第9题：

第10题：

第11题：

第12题：

第13题：

You are planning to import customer data from the Customer table and the Country table in your SQL Server 2000 database into a SQL Server 2005 database. You want to ensure that during the import process，each value in the CountryCode column of the Customer table has a corresponding record in the CountryCode column in the Country table of the SQL Server 2005 database. You define a foreign key between these two tables. Thus，referential integrity will guarantee that the import routine fails if there are any records where a CountryCode value does not exist in the Country table but does exist in the Customer table. You need to ensure that the import process does not fail if records are encountered that do not exist in the Country table. What should you do？（）

• A、Drop the foreign key. Import the data by using the script. Re-create the foreign key.
• B、Create a CHECK constraint.
• C、Create a DML INSTEAD OF trigger that writes the failed records to a file or table.
• D、Create a DML AFTER trigger that writes the failed records to a file or table.

第14题：

You have a range-partitioned table in your database. Each partition in the table contains the sales data for a quarter.  The partition related to the current quarter is modified frequently and other partitions undergo fewer data manipulations. The preferences for the table are set to their default values. You collect statistics for the table using the following command in regular intervals： SQL> EXECUTE  DBMS_STATS.GATHER_TABLE_STATS（’SH’，’SALES’，GRANULARITY=>’GLOBAL’）；   You need statistics to be collected more quickly.  What can you do to achieve this？（）

• A、 Set DYNAMIC_SAMPLING to level 4
• B、 Set the STATISTICS_LEVEL parameter to BASIC
• C、 Set the INCREMENTAL value to TRUE for the partition table
• D、 Increase the value of STALE_PERCENT for the partition table

第15题：

You are investigating the performance of the server and see the following information: Events_waits_summary_global_by_event_name in the performance schema shows that the wait/synch/mutex/sql/LOCK_table_cache event is dominating other wait events. The table_open_cache_overflows status variable is 0. Which action should be taken to remove the performance bottleneck described here?（）

• A、Increase the value of table_definition_cache
• B、Increase the value of table_open_cache_instances
• C、Decrease the value of table_open_cache_instances
• D、Increase the value of table_open_cache
• E、Decrease the value of table_definition_cache
• F、Decrease the value of table_open_cache

第16题：

In your Supportcenter.cn production database，you find that the database users are able to create and read files with unstructured data，available in any location on the host machine from an application. You want to restrict the database users to access files in a specific location on the host machine. What could do to achieve this？（）

• A、Modify the value for the UTL_FILE_DIR parameter in the parameter file
• B、Grant read and write privilege on the operating system path to the database users
• C、Modify the value for the LDAP_DIRECTORY_ACCESS parameter in the parameter file
• D、Modify the value for the PLSQL_NATIVE_LIBRARY_DIR parameter in the parameter file
• E、Create a directory object referring to the operating system path， and grant read and write privilege on the directory object to the database users

第17题：

You are building two forms. Each form has a button and a non-base table field. When the button is pressed, a complicated calculation is executed. The calculation is the same for both forms. The calculation code does not query or change the data in the database. When the calculation completes, it returns a single value to the non-base table field. To optimize performance and maintainability, which PL/SQL structure should be used? （）

• A、A trigger in each form. 
• B、A subprogram in each form. 
• C、A stored subprogram in the database. 
• D、A subprogram in a library that is attached to each form.

第18题：

You are responsible for managing the database schema for an order entry application in a SQL Server 2005 database. After a design review, a member of the development staff asks you to add a new column named CommissionRate to the Product table. Because the actual commission rates for all products are not known at this time, each product has a default commission rate of 12 percent. The rate can be modified as necessary. You add the new column. You need to configure the table to assign the default value as efficiently as possible. What should you do?（）

• A、 Create an INSERT trigger to assign the default value to each item in the table. 
• B、 Create a CHECK constraint to validate the data and to assign the default value to each item in the table. 
• C、 Create an UPDATE trigger to update the default value for each new item in the table. 
• D、 Create a DEFAULT constraint to assign the default value specifying the WITH VALUES argument.

第19题：

第20题：

第21题：

第22题：

第23题：

第24题：