The user SCOTT executes the following command successfully to increase the salary values in one of his sessions：
SQL> UPDATE emp SET sal=sal*1.15 WHERE deptno=20;
Before SCOTT ends the transaction， user HR who has the privileges on EMP table executes a query to fetch the salary details but finds the old salary values instead of the increased values.
Why does HR still see the old data？（）
A.because of redo data from redo log file
B.because of data from database buffer cache
C.because of data from a temporary tablespace
D.because of undo data from the undo tablespace
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Your database is running under automatic undo management and the UNDO_RETENTION parameter is set to 900 sec. You executed the following command to enable retention guarantee：
SQL> ALTER TABLESPACE undotbs1 RETENTION GUARANTEE;
What effect would this statement have on the database？（）
A.The extents in undo tablespace retain data until the next full database backup.
B.The extents containing committed data in the undo tablespace are never overwritten.
C.The extents which no longer contain uncommitted data in the undo tablespace are not overwritten for at least15 minutes.
D.The extents containing committed data in the undo tablespace are not overwritten until the instance is shut down.
A user receives the following error while executing a query：
ORA01555：snapshot too old
Which two options can be the solutions to avoid such errors in future？（）
A.increase the size of redo log files
B.increase the size of the undo tablespace
C.increase the size of the Database Buffer Cache
D.increase the size of the default temporary tablespace
E.enable the retention guarantee for the undo tablespace
User SCOTT executes the following command on the EMP table but has not issued COMMIT， ROLLBACK，or any data definition language （DDL） command：
SQL> SELECT job FROM emp
2 WHERE job=’CLERK’ FOR UPDATE OF empno;
SCOTT has opened another session to work with the database. Which three operations would wait when issued in SCOTT’s second session？（）
A.LOCK TABLE emp IN SHARE MODE;
B.LOCK TABLE emp IN EXCLUSIVE MODE;
C.DELETE FROM emp WHERE job=’MANAGER’;
D.INSERT INTO emp（empno，ename） VALUES （1289，’Dick’）;
E.SELECT job FROM emp WHERE job=’CLERK’ FOR UPDATE OF empno;
A.row level
B.block level
C.object level
D.schema level
E.database level
The ST_INFO master table has millions of rows that are updated very rarely. It has a STATE_CODE column that contains the value for 25 states. The table is frequently queried on the STATE_CODE column.
Which type of index would you suggest to improve the query performance？（）
A.Btree
B.bitmap
C.reverse key
D.function based
A.It fails if any existing row violates the constraint.
B.It does not validate the existing data in the table.
C.It enables the constraint to be enforced at the end of each transaction.
D.It prevents insert， update， and delete operations on the table while the constraint is in the process of being enabled.
Your database is started by using the server parameter file （SPFILE）. You issued this command to change the value of the LOG_BUFFER initialization parameter：
ALTER SYSTEM SET LOG_BUFFER=24M SCOPE=BOTH;
What would be the outcome of this command？（）
A.The command would return an error because LOG_BUFFER is a static parameter.
B.The parameter value would be changed and it would come into effect immediately.
C.You need to restart the database so that parameter changes can come into effect.
D.The command would succeed only if initialization parameter LOG_ARCHIVE_MAX_PROCESS is set to value 2.
You are using flat files as the data source for one of your data warehousing applications. You plan to move the data from the flat file structures to an Oracle database to optimize the application performance. In your database you have clustered tables.
While migrating the data， you want to have minimal impact on the database performance and optimize the data load operation. Which method would you use to load data into Oracle database？（）
A.use the external table population
B.use the Oracle Data Pump export and import utility
C.use the conventional path data load of SQL*Loader utility
D.use the direct path data load of Oracle export and import utility
A.recover using Oracle Flashback Database technology
B.restore the data files from backup and perform a complete recovery
C.restore only the corrupted data file and perform tablespace recovery
D.restore the data files from backup and perform cancelbased recovery
E.restore the entire database from the most recent backup and start the instance and open the database
A.The data files can be recovered till the last committed transaction.
B.The data files can be recovered without shutting down the database.
C.The data file is taken offline automatically; the database remains open.
D.The data files can be recovered to the time of the most recent backup.
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Which statement is true about the loss of systemcritical data files in ARCHIVELOG mode？（）
The user SCOTT executes the following command successfully to increase the salary values in one of his sessions： SQL> UPDATE emp SET sal=sal*1.15 WHERE deptno=20; Before SCOTT ends the transaction， user HR who has the privileges on EMP table executes a query to fetch the salary details but finds the old salary values instead of the increased values. Why does HR still see the old data？（）
Your database is functional with peak load for one hour. You want to preserve the performance statistics collected during this period so that they can be used for comparison while analyzing the performance of the database in the future. What action would you take to achieve this task？（）
In which situation would you use the Oracle Shared Server configuration？（）
A constraint in a table is defined with the INITIALLY IMMEDIATE clause. You executed the ALTER TABLE command with the ENABLE VALIDATE option to enable the constraint that was disabled. What are the two effects of this command？（）
A user receives the following error while executing a query：ORA01555：snapshot too oldWhich two options can be the solutions to avoid such errors in future？（）
While setting up the database for your production environment， you want to create a user with following requirements. 1.The objects created by the user must be stored in a tablespace， TBS1， if the TABLESPACE option is not defined during the object creation. 2.The user should be able to use 10MB of space in the tablespace TBS1. 3.The user must change the password immediately after logging in for the first time. Which three options of the CREATE USER command would you use to achieve this objective？（）
You started a long transaction. Before committing， you executed a query on one of the tables currently being modified. You received the following error： ORA-01555： snapshot too old How would you prevent such an error in the future？（）
When you try to open your database， you receive the following error： ORA-00205： error in identifying control file Where would you find the details required to resolve this error？（）
In your database， the STATISTICS_LEVEL initialization parameter is set to BASIC. What is the impact of this setting？（）