Tag: databases

Questions Related to databases

A tablespace has a table with 30 extents in it. Is this bad?
technology databases

  1. True

  2. False

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Correct Option: B

You need to enforce these two business rules: 1. No two rows of a table can have duplicate values in the specified column. 2. A column cannot contain null values. Which type of constraint ensure that both of the above rules are true ?
technology databases

  1. Check

  2. Unique

  3. Not Null

  4. Primary Key

  5. Foreign Key

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Correct Option: D

CREATE TABLESPACE user_data DATAFILE '/u01/oradata/user_data_01.dbf' SIZE 100M LOCALLY MANAGED UNIFORM SIZE 1M AUTOMATIC SEGMENT SPACE MANAGEMENT; Which part of the tablespace will be of a uniform size of 1 MB?
technology databases

  1. Extent

  2. Segement

  3. Oracle block

  4. Operating system block

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Correct Option: A

The ORDERS table has a constant transaction load 24 hours a day, so down time is not allowed. The index become fragmented. Whic statment is true ?
technology databases

  1. The index need to be dropped, and then re-created.

  2. The resolution of index fragmentation depends on the type of index.

  3. The index can be rebuilt while users continue working on the table.

  4. The index can be rebuilt, but users will not have access to the index during this time.

  5. The fragmented can be ignored because Oracle resolve index fragmentation by means of a freelist.

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Correct Option: C

You need to enforce these two business rules: 1. No two rows of a table can have duplicate values in the specified column. 2. A column cannot contain null values. Which type of constraint ensure that both of the above rules are true ?

technology databases

  1. Check

  2. Unique

  3. Not Null

  4. Primary Key

  5. Foreign Key

Show answer
Correct Option: D

You omit the UNDO tablespace clause in your CREATE DATABASE statment. The UNDO_MANAGEMENT parameter is set to AUTO. What is the result of your CREATE DATABASE statement ?
technology databases

  1. The oracle server creates no undo tablespace.

  2. The oracle server creates an undo segment in the system tablespace.

  3. The oracle server cerates one undo tablespace with the name SYS_UNDOTBS.

  4. Database creation fails because you did not specify an undo tablespace on the create database statment.

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Correct Option: C

John has created a procedure named SALARY_CALC. Which SQL query allow him to view text of procedure?
technology databases

  1. SELECT text FROM user_source WHERE name = 'SALARY_CALC';

  2. SELECT * FROM user_source WHERE name='SALARY_CALC';

  3. SELECT * FROM user_objects WHERE object_name='SALARY_CALC';

  4. SELECT * FROM user_procedures WHERE object_name='SALARY_CALC';

  5. SELECT text FROM user_source WHERE name='SALARY_CALC' and owner='JOHN'

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Correct Option: A

What should you look at to compute the number of undo blocks written per second on disk ?
technology databases

  1. V$UNDOSTAT

  2. V$TRANSACTION

  3. V$ROLLSTAT

  4. DBA_UNDO_EXTENTS

  5. DBA_ROLLBACK_SEGS

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Correct Option: A

You discover that a disk failure occured on DISK3 where the data file belonging to the USER_DATA table is stored. The database is currently open and you need to recover the data file. You will restore the data file to DISK2. what is the correct sequence RMAN commands to restore and recover the data file ?
technology databases

  1. RUN { RESTORE TABLESPACE user_data; RECOVER TABLESPACE user_data; ALTER DATABASE OPEN; }

  2. RUN { ET NEWNAME FOR '/DISK3/user_data01.dbf' TO '/DISK2/user_data01.dbf'; RESTORE TABLESPACE user_data; SWITCH DATAFILE '/DISK3/user_data01.dbf';

  3. RUN { RESTORE TABLESPACE user_data; SET NEWNAME FOR '/DISK3/user_data01.dbf' TO '/DISK2/user_data01.dbf'; SWITCH DATAFILE '/DISK3/user_data01.dbf';

  4. RUN { SET NEWNAME FOR '/DISK3/user_data01.dbf' TO '/DISK2/user_data01.dbf'; RESTORE TABLESPACE user_data; RECOVER TABLESPACE user_data; ALTER DATABASE OPEN;}

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Correct Option: B

When performing an incomplete recovery of the whole database, what must be true about the data files that are restored ?
technology databases

  1. All of the data files must be from a backup taken prior to the point in time to which you want to recover.

  2. Only the data files belonging from the SYSTEM tablespace must be from a backup taken prior to the point in time to which you want to recover.

  3. Only the data files that need recovery must be from a backup taken prior to the point in time which you want to recover.

  4. Only the data files belonging to the SYSTEM tablespace and the data files that need recovery must be from a backup taken prior to the point in time to which you want to recover.

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Correct Option: A