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.

E-R Model ConceptsBackup and RecoverySQL Server UpgradesJDBC and ODBCBig Data CharacteristicsData VirtualizationOracle Database

Database Management Systems Questions

Multiple choice

Which of the following is/are true about log writer in the Oracle database server?

  1. It is used to store log records for recovery process.

  2. Log writer is responsible for writing the redo log buffer to the redo log files.

  3. The typical size of log writer is up to a few hundred kilobytes.

  4. All of the above

  5. Both (1) and (2)
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Log writer is a background process and is responsible for writing the redo log buffer to redo log files.

Multiple choice

Which of the following is/are true about the multitier architecture of Oracle database?

  1. Multitier Architecture contains one or more application servers.

  2. An application server acts as an interface between clients and multiple database servers.

  3. Multitier architecture enables application server to validate the credentials of a client, such as a web browser.

  4. All of the above

  5. Both (1) and (3)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

All these are the correct statements.

Multiple choice

Which of the following is false about Oracle instance in Oracle database server?

  1. Oracle instance is a major component in the Oracle database server.

  2. Oracle instance is a set of memory and process structures.

  3. It is responsible for translating SQL calls given by the client.

  4. Oracle instance may exist without being associated with an Oracle database.

  5. None of the above
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

All of the above are the true statements.

Multiple choice

How to create a backup copy of table emp called emp_backup in another database called DBEmp_backup.mdb?

  1. CREATE TABLE DBEmp_backup.emp_backup FROM emp

  2. SELECT emp.* INTO emp_backup IN DBEmp_backup.mdb FROM emp

  3. CREATE TABLE emp_backup IN DBEmp_backup.mdb FROM emp

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The SELECT...INTO statement is the correct SQL syntax to create a new table in another database from existing data. Options A and C use invalid CREATE TABLE syntax (no FROM clause in this context).

Multiple choice

What is DDL?

  1. Data Dictionary Language

  2. Data Definition language

  3. Data Declaration Language

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

DDL stands for Data Definition Language, the subset of SQL commands that define database structures (CREATE, DROP, ALTER). DML manipulates data, DCL controls permissions, and TCL manages transactions.

Multiple choice

Which of the following is/are correct about Data Virtualization?

  1. This virtualization allows user to access the same information from multiple physical locations.

  2. In this virtualization, several other storage devices are combined into one virtual environment.

  3. This virtualization allows users to run any type of operating systems.

  4. This virtualization use virtual machines to managed data.

  5. Both (2) and (3)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This is true as Data virtualization moves the data to a server, maps it to its original location and allows users to view it.

Multiple choice

Which of the following technologies helps you to write Java applications that manage the activities such as connecting to a data source, sending queries, updating statements to the database etc.?

  1. JDBC API

  2. JDBC driver manager

  3. JDBC-ODBC bridge

  4. JDBC URL

  5. excuteQuery()
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

It helps you to write java applications that manage the activities such as connecting to a data source, sending queries, updating statements to the database etc....

Multiple choice

Which of the following nodes participating in the session tree sends all of the distributed transaction's SQL statements, remote procedure calls and so forth to the directly reference nodes?

  1. Local coordinator

  2. Global coordinator

  3. Database server

  4. Client

  5. Shared mode

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This node participating in the session tree sends all of the distributed transaction's SQL statements, remote procedure call and so forth to the directly reference nodes.

Multiple choice

Which of the following features of the RMAN describes the contents of the backup set that define which files are multiplexed and the level of multiplexing?

  1. Proxy archived log backups

  2. Recovery through Resetlogs

  3. Automatic datafiles creation

  4. Detection of failure

  5. Disk topology and automatic performance tuning

Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

This feature of the RMAN describes the contents of the backup sets that define which files are multiplexed and the level of multiplexing.