单选题Which of the following best describes how locks are used in DB2?（）A To maintain control of updated rows for commit processingB To ensure only committed changes are altered by another applicationC To allow two applications to update the same row of data

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.

第2题：

A technician needs to troubleshoot connectivity between two devices located on the same network. Which of the following BEST describes the type of protocol being used?（）

• A、IGP
• B、EIGRP
• C、EGP
• D、BGP

第3题：

第4题：

Which of the following can be used to ensure that once a row has been inserted in table TABLEX, the column MAINID in that row cannot be updated?（）

• A、Define the column MAINID as NOT UPDATABLE
• B、Define the column MAINID as a PRIMARY KEY
• C、Define the column MAINID as a FOREIGN KEY
• D、Define an UPDATE trigger on table TABLEX

第5题：

Which of the following best describes the lock protection provided by DB2 for the current row of a cursor?（）

• A、The cursor is only protected from updates and deletes by concurrent applications.
• B、The row is only protected from positioned updates and deletes that reference another cursor of the same application.
• C、The cursor is protected from positioned updates and deletes that reference another cursor of a different application.
• D、The row is protected from updates and deletes by the current application and from positioned updates and deletes that reference another cursor of the same application.

第6题：

A server has a processor that allows it to calculate two applications at the same time. Which of the following describes this capability of the processor?（）

• A、Dual processing
• B、Multi-processing
• C、Multi-tasking
• D、Multi-threading

第7题：

Which of the following is TRUE for the DB2 isolation level Cursor Stability (CS)?（）

• A、An application process acquires at least a share lock on the current row of every cursor.
• B、Any row that is read during a unit of work cannot be changed by other application processes until the unit of work is complete.
• C、Any row changed by another application process can be read, even if the change has not been committed by that application process.
• D、An application process that issues the same query more than once in a unit of work will not see additional rows caused by other application processes appending new information to the database.

第8题：

第9题：

How does DB2 protect the integrity of indexes when data is updated?（）

• A、Locks are acquired on the data.
• B、Locks are acquired on index keys.
• C、Locks are acquired on index pages.
• D、Locks are acquired on index pointers.

第10题：

Which of the following describes how DB2 9 stores an XML document if the XML Extender is not used?（）

• A、CLOB
• B、BLOB
• C、Hierarchically
• D、Rows and columns