Computer Knowledge

Database Management Systems

5,344 Questions

Database Management Systems (DBMS) form the core framework for data storage, retrieval, and security in modern software applications. Concepts such as the E-R model, backup planning, SQL integration, and big data architecture are essential for computer knowledge sections. This hub offers a comprehensive set of practice questions to master DBMS fundamentals and advanced database operations.

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Database Management Systems Questions

Multiple choice technology databases

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

  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.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

For an incomplete database recovery, all restored data files must be from backups taken prior to the target point-in-time to allow the recovery process to roll forward to the desired state.

Multiple choice technology databases

You have performed the first step in placing your database into ARCHIVELOG mode. The second step is deciding whether the online redo log files are to be archived automatically or manually. which action should you take to enable archiving an instance startup?

  1. Set the LOG_ARCHIVE_START parameter to TRUE in the initialization parameter file.

  2. Automatic archive is the default when ARCHIVELOG mode is set. No further actions are required.

  3. Set the LOG_ARCHIVE_MAX_PROCESSES parameter to n (where n is the number of Archiver process) in the initialization parameter file.

  4. Immediately after setting the database in ARCHIVELOG mode, in SQL*Plus select automatic archiving using the syntax : ALTER DATABASE SET LOG_ARCHIVE_START=TRUE
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The LOG_ARCHIVE_START parameter controls automatic archiving at instance startup. Setting it to TRUE in the initialization parameter file enables automatic archiving when the instance starts. Option B is incorrect because automatic archiving is not the default - you must explicitly enable it. Option C sets the number of archiver processes but doesn't enable automatic archiving. Option D is incorrect because LOG_ARCHIVE_START is an initialization parameter, not set dynamically with ALTER DATABASE.

Multiple choice technology databases

You issue this statement ALTER DATABASE BACKUP CONTROLFILE TO TRACE; What does the statment generate ?

  1. A text copy of the control file.

  2. A binary copy of the control file.

  3. A file containing a SQL statement which will re-create the database.

  4. A file containing a SQL statement which will re-create the control file.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

ALTER DATABASE BACKUP CONTROLFILE TO TRACE generates a trace file in the user_dump_dest directory containing SQL commands to recreate the control file. This is useful for recovery or documentation purposes. Option A is incorrect because it's not a direct text copy of the control file - it's SQL to recreate it. Option B is wrong because it's not a binary copy. Option C is incorrect because it recreates the control file, not the entire database.

Multiple choice technology databases

Which statement is true regarding RMAN components?

  1. Each target database requires its own recover catalog.

  2. RMAN scripts can be stored in the recovery catalog or the targer control file.

  3. A channel is a stream of data to a device type and corresponds to one server session.

  4. The RMAN executable interprets server session commands and establishes connections to the target database.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

An RMAN channel represents a stream of data to a device type and corresponds to one server session on the target database instance. Other options are incorrect because target databases do not require individual catalogs, and scripts cannot be stored in the control file.

Multiple choice technology databases

You plan to take a closed database backup using operating system commands. Which three SHUTDOWN options are appropriate for this type of backup? (Choose three)

  1. ABORT

  2. NORMAL

  3. IMMEDIATE

  4. TRANSACTIONAL
Reveal answer Fill a bubble to check yourself
B,C,D Correct answer
Explanation

For a consistent closed database backup using OS commands, use NORMAL, IMMEDIATE, or TRANSACTIONAL shutdown options. These ensure all transactions are complete and the database is cleanly closed. NORMAL waits for all users to disconnect. IMMEDIATE rolls back active transactions and disconnects users. TRANSACTIONAL waits for active transactions to finish. ABORT is unsafe for backup as it doesn't cleanly close the database - it's equivalent to pulling the plug.

Multiple choice technology databases

Which three attributes of the LOG_ARCHIVE_DEST_n initialization parameter control the data availability mode of a Data Guard standby database? (Choose three)

  1. SYNC or ASYNC to identify the network transmission mode.

  2. LGWR or ARCH to identify the primary database process responsible for sending redo information to the standby.

  3. AFFIRM or NOAFFIRM to control whether log archiving disk write operations are to be performed synchronously or asynchronously.

  4. PROTECTED or UNPROTECTED to control the degree of divergence and data loss at the standby database.
Reveal answer Fill a bubble to check yourself
A,B,C Correct answer
Explanation

The LOG_ARCHIVE_DEST_n parameters use SYNC/ASYNC for network transmission mode (synchronous or asynchronous), LGWR/ARCH to specify which primary process sends redo (LGWR for real-time, ARCH for archiver), and AFFIRM/NOAFFIRM to control whether disk writes are synchronous (AFFIRM) or asynchronous (NOAFFIRM). These three attributes directly control data availability and protection modes in Data Guard. Option D mentions PROTECTED/UNPROTECTED which are high-level availability modes, not individual parameters.

Multiple choice technology databases

When an oracle Instance is started, background process are started. Background processes perform which two functions ? (Choose two)

  1. Perform I/O

  2. Lock rows that are not data dictionary rows

  3. Monitor other Oracle processes

  4. Connect users to the Oracle instance

  5. Execute SQL statments issued through an application
Reveal answer Fill a bubble to check yourself
A,C Correct answer
Explanation

Oracle background processes perform specialized I/O operations (like DBWn writing dirty buffers) and monitor other Oracle processes (like PMON cleaning up failed processes, SMON performing recovery). These functions are separated from user processes to improve efficiency.

Multiple choice technology databases

Which three are the physical structures that constiture the Oracle database ? (Choose Three)

  1. Control file

  2. Extent

  3. Segment

  4. Data file

  5. Log file

  6. Tablespace
Reveal answer Fill a bubble to check yourself
A,D,E Correct answer
Explanation

The Oracle database's physical storage structures are control files (containing metadata and database structure), data files (storing actual table/index data), and online redo log files (recording all changes for recovery). Tablespaces and segments are logical structures, not physical ones.

Multiple choice technology databases

SQL> CREATE TABLESPACE user_data EXTENT MANAGEMENT LOCAL SEGMENT SPACE MANAGEMENT AUTO; Which twp assumptions must be true for this statement to execute successfully ? (Choose two)

  1. Oracle Managed Files used for this instance.
  2. The USER_DATA tablespace in managed using FET$/UET$ tables.

  3. The COMPATIBLE intialization paramter must be 9.0.0 or higer.

  4. Space within segments is the USER_DATA tablespace is managed with freelists.
Reveal answer Fill a bubble to check yourself
A,C Correct answer
Multiple choice technology databases

Which two statments regarding the control file and Recover Manager are true ? (Choose two)

  1. The control file can grow in size.

  2. The control file can store RMAN scripts.

  3. CONTROL_FILE_RECORD_KEEP_TIME determine retention time for RMAN records.

  4. The RMAN catalog can exist solely in the control file of the target database.
Reveal answer Fill a bubble to check yourself
C,D Correct answer
Explanation

CONTROL_FILE_RECORD_KEEP_TIME (C) determines how long RMAN records are retained in the control file. The RMAN catalog can exist solely in the control file (D) for the target database, though a separate recovery catalog database is recommended for production environments.

Multiple choice technology databases

The database is running in NOARCHIVELOG mode. A data file is lost. Which two are valid options for recover ? (Choose two)

  1. Restore the data file and perform incomplete recovery.

  2. Restore the data file and perform point-in-time recover.

  3. Drop the tablespace and lose all data in the tablespace.

  4. Restore the database and lose all data since the last backup.
Reveal answer Fill a bubble to check yourself
C,D Correct answer
Explanation

In NOARCHIVELOG mode, Oracle does not archive redo logs, so you cannot perform media recovery (incomplete or point-in-time) which requires archived logs. The only valid options are: (1) dropping the tablespace and losing only its data, or (2) restoring the entire database from the last backup and losing all changes since that backup. Options A and B are invalid because they require archived redo logs for recovery.

Multiple choice technology databases

What file will give you Oracle instance status information?

  1. alert.ora

  2. init.ora

  3. tnsname.ora

  4. redolog
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The alert log file (alert.ora or alert.log) is the primary location for Oracle instance status information, recording startup/shutdown events, errors, and significant operational messages. The init.ora file contains initialization parameters, tnsnames.ora handles network configuration, and redo logs store transaction changes - none provide instance status.

Multiple choice technology enterprise content management

All content within a channel share the same

  1. Content attributes (schema)

  2. Workflow steps

  3. Publishing Lifecycle

  4. Display options
Reveal answer Fill a bubble to check yourself
A,B,C,D Correct answer
Explanation

In Oracle WebCenter Content / Stellent Information Manager, all content items within a specific channel share the same content attributes (schema), workflow steps, publishing lifecycle, and display options. Thus, all options are correct.

Multiple choice technology mainframe

What is meant by local DB2?

  1. The DB2 application server in which the application's plan is bound is known as local DB2.

  2. The DB2 application server in which the application's package is bound is known as local DB2.

  3. The DB2 application server in which the application's load is bound is known as local DB2.

  4. None of the Above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In DB2 terminology, the local DB2 is the application server where the application's plan is bound. A plan contains the bound SQL statements and access paths that the application will use. Package binding is a different concept related to DB2.