Tag: databases

Questions Related to databases

Which statements are true regarding the logical structure of database? (Choose three)
technology databases

  1. It is possible to have tablespaces of different block sizes in a database.

  2. A data block is the smallest unit of I/O for data files.

  3. Multiple tablespaces can share single data file.

  4. Each data block in the database always corresponds to one OS block.

  5. Each segment contains one or more extents.

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Correct Option: A,B,E

Which three statements are true about the stages of database startup?
technology databases

  1. Data files and redo log files can be renamed at the MOUNT stage.

  2. Control files are required to bring the database to the NOMOUNT stage.

  3. Data files and online redo log files are checked for consistency while opening the database.

  4. Data files and redo log files are made available to users at the OPEN stage.

  5. Control files are read at the OPEN stage for the location of data files.

Show answer
Correct Option: A,B,D

Identify two tablespaces whose data files are so critical that only a closed recovery is possible?
technology databases

  1. USERS

  2. TOOLS

  3. UNDO

  4. INDEX

  5. SYSTEM

Show answer
Correct Option: C,E
Explanation:

To solve this question, the user needs to know about the concept of tablespaces and recovery methods in Oracle database.

Closed recovery is a type of database recovery method in which all the data files of the database are restored from a backup and then the redo logs are applied to bring the database to a consistent state. Closed recovery is required when the database is in a state of complete failure and no data is available in the memory structures.

Only those tablespaces whose data files are so critical that they cannot be recovered using an open recovery method require a closed recovery.

Now, let's go through each option and identify if it requires a closed recovery or not:

A. USERS: This tablespace contains the user's data. It does not require a closed recovery if it gets damaged because it can be restored using an open recovery method.

B. TOOLS: This tablespace contains the database tools data. It does not require a closed recovery if it gets damaged because it can be restored using an open recovery method.

C. UNDO: This tablespace contains the undo data. It does not require a closed recovery if it gets damaged because it can be restored using an open recovery method.

D. INDEX: This tablespace contains the database index data. It does not require a closed recovery if it gets damaged because it can be restored using an open recovery method.

E. SYSTEM: This tablespace contains the system data. It is critical to the functioning of the database. If its data files are damaged, a closed recovery is required to restore it from a backup.

Therefore, the correct answer is:

The Answer is: E (SYSTEM)

Data files of which three tablespaces can be recovered by performing an open recovery?
technology databases

  1. TEMP

  2. UNDO

  3. INDEX

  4. SYSAUX

  5. SYSTEM

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Correct Option: A,C,D

While running OUI on a UNIX platform to install Oracle 10g software you are prompted to run orainstRoot.sh script. What does this script accomplish?
technology databases

  1. It creates the pointer file

  2. It creates the base directory

  3. It creates the inventory pointer file

  4. It creates the oracle user for installation.

  5. It modifies the UNIX kernel parameters to match oracle’s requirements.

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Correct Option: C

You want to perform a backup of your database to a tape. Which backup format can you use?

technology databases

  1. backup set only

  2. image copy only

  3. only user-managed backup

  4. both image copy and backup set

  5. only incremental image copy backup

Show answer
Correct Option: A

AI Explanation

To answer this question, you need to understand the different backup formats used for database backups.

Option A) backup set only - This option is correct because a backup set is a logical backup format that can be written to tape. It includes all the necessary data and metadata to restore the database.

Option B) image copy only - This option is incorrect because an image copy is a physical backup format that cannot be written directly to tape. It is a bit-for-bit copy of the database files and is typically used for faster recovery.

Option C) only user-managed backup - This option is incorrect because it does not specify a specific backup format. User-managed backup refers to the process of manually performing backups, but it does not specify the format.

Option D) both image copy and backup set - This option is incorrect because although both backup sets and image copies are valid backup formats, only the backup set can be used for writing to tape as specified in the question.

Option E) only incremental image copy backup - This option is incorrect because it specifies a specific type of backup (incremental image copy) rather than a format. Incremental backups only copy the changes made since the last backup and do not provide a full backup of the database.

Therefore, the correct answer is option A) backup set only. This option is correct because a backup set is a logical backup format that can be written to tape.

One user session was terminated abnormally in the middle of a transaction What does oracle database do to recover it?
technology databases

  1. uses undo data for roll forward

  2. uses flashback log for recovery

  3. uses online redo logs to roll back

  4. uses undo data to roll back the transaction

  5. uses recovery managers (RMAN) to roll back.

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Correct Option: D

You are using the following command to clear the log file group ALTER DATABASE CLEAR LOGFILE GROUP 2; In which case would the command be successful?
technology databases

  1. Group 2 is the active group

  2. Group 2 is the current group

  3. Database is in the MOUNT stage

  4. Group 2 has been already archived

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Correct Option: D

Users in PROD database reported about the slow responses of the transaction. While investigating the reason you find that the transactions are waiting for the undo segments to be available, and undo retention has been set to zero. What would you do to overcome this problem?
technology databases

  1. increase the undo retention

  2. create more undo segments

  3. create another undo tablespace

  4. increase the size of the undo tablespace.

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Correct Option: D

Your application demands frequent connection and disconnection from the database. You have three listener processes those are listening for the database PROD. While settings up connect string using Oracle Enterprise Manager 10g Database Control, which two options would you select to balance the connection load across all the listener process? (Choose two)

technology databases

  1. Use only the first address.

  2. Try one address selected at random.

  3. Try each address, in order, until one succeeds.

  4. Try each address, randomly, until one succeeds.

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Correct Option: B,D