IBM IBM Certified Database Associate C2090-730 Questions & Answers

• Question 31:

  Which of the following resources can be explicitly locked?

  A. Row

  B. Page

  C. Table

  D. Column

  Correct Answer: C

• Question 32:

  A table contains a list of all seats available at a football stadium. A seat consists of a section number, a seat number, and whether or not the seat has been assigned. A ticket agent working at the box office generates a list of all unassigned seats. When the agent refreshes the list, it should only change if another agent assigns one or more unassigned seats. Which of the following is the best isolation level to use for this application?

  A. Repeatable Read

  B. Read Stability

  C. Cursor Stability

  D. Uncommitted Read

  Correct Answer: C

• Question 33:

  Application A issues the following SQL statements within a single transaction using the Uncommitted Read

  isolation level:

  SELECT * FROM department WHERE deptno = 'A00';

  UPDATE department SET mgrno = '000100' WHERE deptno = 'A00';

  As long as the transaction is not committed, which of the following statements is FALSE?

  A. Other applications not running under the Uncommitted Read isolation level are prohibited from reading the updated row

  B. Application A is allowed to read data stored in another table, even if an Exclusive lock is held on that table

  C. Other applications running under the Uncommitted Read isolation level are allowed to read the updated row

  D. Application A is not allowed to insert new rows into the DEPARTMENT table as long as the current transaction remains active

  Correct Answer: D

• Question 34:

  Application A wants to read a subset of rows from table TAB1 multiple times. Which of the following isolation levels should Application A use to prevent other users from making modifications and additions to table TAB1 that will affect the subset of rows read?

  A. Repeatable Read

  B. Read Stability

  C. Cursor Stability

  D. Uncommitted Read

  Correct Answer: A

• Question 35:

  An application has acquired a Share lock on a row in a table and now wishes to update the row. Which of the following statements is true?

  A. The application must release the row-level Share lock it holds and acquire an Update lock on the row

  B. The application must release the row-level Share lock it holds and acquire an Update lock on the table

  C. The row-level Share lock will automatically be converted to a row-level Update lock

  D. The row-level Share lock will automatically be escalated to a table-level Update lock

  Correct Answer: C

• Question 36:

  Which of the following modes, when used with the LOCK TABLE statement, will cause the DB2 Database Manager to acquire a table-level lock that prevents other concurrent transactions from accessing data stored in the table while the owning transaction is active?

  A. SHARE MODE

  B. ISOLATED MODE

  C. EXCLUSIVE MODE

  D. RESTRICT MODE

  Correct Answer: C

• Question 37:

  To which of the following resources can a lock NOT be applied?

  A. Table spaces

  B. Buffer pools

  C. Tables

  D. Rows

  Correct Answer: B

• Question 38:

  Which of the following causes a lock that is being held by an application using the Cursor Stability isolation level to be released?

  A. The cursor is moved to another row

  B. The row the cursor is on is deleted by the application

  C. The row the cursor is on is deleted by another application

  D. The row the cursor is on needs to be updated by another application

  Correct Answer: A

• Question 39:

  Application A holds a lock on a row in table TAB1. If lock timeout is set to 20, what will happen when Application B attempts to acquire a compatible lock on the same row?

  A. Application B will acquire the lock it needs

  B. Application A will be rolled back if it still holds its lock after 20 seconds have elapsed

  C. Application B will be rolled back if Application A still holds its lock after 20 seconds have elapsed

  D. Both applications will be rolled back if Application A still holds its lock after 20 seconds have elapsed

  Correct Answer: A

• Question 40:

  Which of the following DB2 UDB isolation levels will only lock rows during read processing if another transaction tries to drop the table the rows are being read from?

  A. Repeatable Read

  B. Read Stability

  C. Cursor Stability

  D. Uncommitted Read

  Correct Answer: D