单项选择题

Which object may be used during query optimization to improve the performance for a subset of SELECT queries?（）

A.MQT
B.Trigger
C.Read Only Cursor
D.Stored Procedure

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单项选择题

To which of the following resources can a lock be applied?（）

A.Row
B.Alias
C.Bitmap
D.Column

单项选择题

Application A holds an Update lock on a single row and application B is trying to read that row. If both applications are using isolation level UR, which of the following will occur?（）

A.Application B will read the row.
B.Applications A and B will cause a deadlock situation.
C.Application B will wait until application A releases the Update lock.
D.Application A will be terminated so that application B can read the row.

单项选择题

Application A is designed to execute the following SQL statements within a single Unit of Work (UOW).
UPDATE employee SET salary = salary * 1.1 WHERE empno='000010' UPDATE department SET deptname = 'NEW dept' WHERE deptno='A00'Application B is designed to execute the following SQL statements within a single Unit of Work (UOW). UPDATE department SET deptname = 'OLD DEPT' WHERE deptno='A00' UPDATE employee SET salary = salary * 0.5 WHERE empno='000010'
Application A and application B execute their first SQL statement at the same time. When application A and application B try to execute their second SQL statement, a deadlock occurs.
What will happen?（）

A.The database manager will rollback the transaction in both applications.
B.The database manager will rollback the transaction in one of the two applications.
C.Application B will successfully update the EMPLOYEE and DEPARTMENT tables; Application A will be placed in a lock wait state.
D.Application A will successfully update the EMPLOYEE and DEPARTMENT tables; Application B will terminate when the lock timeout value is reached.