Free Oracle 1Z0-042 Exam Dumps Questions & Answers

You require the Oracle server to manage the undo segments and space among various active sessions automatically. You created an undo tablespace, UNDO_TBS1, in your database. Which two additional steps would you perform to achieve this? (Choose two.)

• A.  Set the UNDO_TABLESPACE parameter to UNDO_TBS1.
• B.  Set the UNDO_RETENTION parameter to 900 or more.
• C.  Create an initial undo segment in the undo tablespace.
• D.  Set the UNDO_MANAGEMENT initialization parameter to AUTO.
• E.  Enable the retention guarantee for the undo tablespace.

Which three statements are true about the stages of database startup? (Choose three.)

• A.  Data files and redo log files can be renamed at the MOUNT stage.
• B.  Data files and redo log files are made available to users at the OPEN stage.
• C.  Control files are required to bring the database to the NOMOUNT stage.
• D.  Control files are read at the OPEN stage for the location of data files.
• E.  Data files and online redo log files are checked for consistency while opening the database.

What are the consequences of executing the SHUTDOWN ABORT command? (Choose two.)

• A.  The database is closed, but the instance is still started.
• B.  Database buffers and redo buffers are not written to the disk.
• C.  The database undergoes automatic media recovery during the next startup.
• D.  Uncommitted changes are not rolled back.
• E.  The database files are synchronized.

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 data from database buffer cache
• B.  because of undo data from the undo tablespace
• C.  because of redo data from redo log file
• D.  because of data from a temporary tablespace

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? (Choose two.)

• A.  It does not validate the existing data in the table.
• B.  It prevents insert, update, and delete operations on the table while the constraint is in the process of being enabled.
• C.  It fails if any existing row violates the constraint.
• D.  It enables the constraint to be enforced at the end of each transaction.