Computer Knowledge

Database Management Systems

5,543 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 statement(s) about Oracle database?

  1. Ordinary tables are stored with all rows in no particular order.

  2. In ordinary tables, rows of the table are stored in different segments.

  3. In partitioned tables, rows of the table are stored in one segment.

  4. All of the above

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

Ordinary tables have no partition in their structures so they don't have any particular keys also. Hence their order is not maintained.

Multiple choice

Which of the following is a false statement about the Application architecture in Oracle database?

  1. In Application architecture, client application is also responsible for data processing.

  2. Oracle database provides better performance to its client applications.

  3. Oracle database provides better concurrency and data integrity.

  4. Client applications are not dependent on the physical location of the data.

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

Client application is not responsible for data processing rather it is responsible for request input from the user and data form the server.

Multiple choice

Which of the following is/are the false statement(s)?

  1. System Global Area (SGA) has no direct access from the clients.

  2. System Global Area (SGA) is a called a shared memory segment.

  3. The dictionary cache in SGA caches Oracle own internal information.

  4. None of the above

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

All are the true statements.

Multiple choice

Which of the following is a false statement about the data flow in Oracle database?

  1. The log buffer is responsible for records all the changes made to the buffer cache.

  2. The log buffer is a part of SGA (System Global Area).

  3. The serve process makes an entry to log buffer to execute the SQL statements.

  4. The log buffer is not responsible to redo the changes in case of a recovery process.

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

This is a false statement as log buffer records all changes made to buffer cache and these changes can be done again  in the recovery process.

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

Matrices are often used to organize data for business and

  1. fortran language

  2. scientific applications

  3. binary coding

  4. none of these

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

Matrices are widely used to organize data for business applications like financial modeling, inventory management, and scientific applications including physics simulations, statistical analysis, and engineering calculations. Their grid structure efficiently represents multi-dimensional data and transformations.

Multiple choice

Which one of the following is not correctly matched?

  1. MAtDB: a model organism database for Arabidopsis

  2. BLAST: A comprehensive database for the study of human genetics and molecular biology

  3. PROSITE: First secondary database developed

  4. Entrez: An information retrieval tool of NCBI GenBank

  5. DDBJ: A biological database that collects DNA sequences
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Basic Local Alignment Search Tool (BLAST) is an algorithm for comparing primary biological sequence information.

Multiple choice

INSD consists of which among the following databases?

  1. DNA Data Bank of Japan
  2. European Nucleotide Archive
  3. GenBank
  4. PROSITE
  5. VectorBase

  1. 1, 2 and 3

  2. 1, 3 and 5

  3. 2, 3 and 4

  4. 2, 4 and 5

  5. 3, 4 and 5
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The International Nucleotide Sequence Database Collaboration (INSDC) consists of a joint effort to collect and disseminate databases containing DNA and RNA sequences. It consists of the following databases: DNA Data Bank of Japan (Japan), GenBank (USA) and the European Nucleotide Archive (UK).

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....