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
  1. sp_rename TableNewName, ExistingTableName;

  2. sp_renametable ExistingTableName, TableNewName;

  3. sp_rename ExistingTableName, TableNewName;

  4. sp_renametable TableNewName, ExistingTableName;

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

sp_rename 'OldName', 'NewName' is the correct system stored procedure to rename a table (or other database objects). The first parameter is the current name, the second is the new name. Options A and D reverse the order, and sp_renametable doesn't exist - only sp_rename.

Multiple choice technology databases
  1. Records

  2. Fields

  3. Attributes

  4. Cardinality

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

In relational database terminology, a horizontal row in a table is called a record (or sometimes tuple). Fields refer to the vertical columns that contain attributes. Cardinality refers to the number of rows in a table.

Multiple choice technology databases
  1. Data Mode Lane

  2. Data Manipulation language

  3. Data Model Language

  4. Different Mode Level

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

DML stands for Data Manipulation Language, the subset of SQL used for manipulating data. It includes commands like INSERT, UPDATE, DELETE, and SELECT for querying and modifying the data stored in database tables.

Multiple choice technology mainframe
  1. RR

  2. RS

  3. UR

  4. CS

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

UR (Uncommitted Read) isolation level provides maximum data concurrency while preventing access to uncommitted data. This is achieved by allowing transactions to read data that other transactions have modified but not yet committed, while still protecting against reading uncommitted changes. RS (Read Stability), CS (Cursor Stability), and RR (Repeatable Read) are more restrictive levels that reduce concurrency to prevent various types of phenomena like non-repeatable reads and phantom reads.

Multiple choice technology mainframe
  1. db2look

  2. db2move

  3. reorg

  4. runstats

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

The REORG utility is specifically designed to reorganize table data, reclaiming space from deleted rows and improving access patterns by physically reordering data on disk. db2look is for DDL extraction, db2move is for data movement/export/import, and runstats is for updating table statistics used by the query optimizer. REORG is the correct tool for the stated purpose of space reclamation through data reorganization.

Multiple choice technology mainframe
  1. Read Stability

  2. Cursor Stability

  3. Repeatable Read

  4. Uncommitted Read

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

Repeatable Read (RR) isolation level is designed to prevent phantom reads, which during an index scan requires acquiring a table-level lock to prevent other transactions from inserting or modifying rows that would affect the scan results. Read Stability (RS) and Cursor Stability (CS) use less restrictive locking at the row or page level. Uncommitted Read (UR) acquires minimal locks. The table-level lock in RR ensures that the set of rows matching a query remains consistent throughout the transaction.

Multiple choice technology mainframe
  1. Journal

  2. Alert Center

  3. License Center

  4. Client Configuration Assistant

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

The Client Configuration Assistant (CCA) is a DB2 tool used to catalog databases, which involves registering database connection information in the client's configuration. Journal, Alert Center, and License Center are not tools for cataloging databases - they serve different administrative or monitoring purposes. Cataloging is essential for clients to locate and connect to databases on the network.

Multiple choice technology mainframe
  1. SYSMAINT

  2. SYSCTRL

  3. DBCTRL

  4. SYSADM

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

SYSCTRL authority has the privilege to create databases in DB2. SYSMAINT can perform maintenance operations but cannot create databases. DBCTRL is not a standard DB2 authority level. While SYSADM (System Administrator) has all privileges including database creation, the question specifically asks for which authority CAN create a database, and SYSCTRL is the minimal authority with this privilege. The answer key is correct.

Multiple choice technology mainframe
  1. Memory usage is reduced

  2. Query compilation time is reduced

  3. Data access time is increased

  4. Data access control is increased

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

Views are virtual tables that enhance data security and access control by limiting what data users can see or modify. By creating a view on a table, administrators can grant users access only to specific rows or columns, effectively increasing control over data access. Views do not reduce memory usage (they store no data), do not reduce compilation time (queries are still compiled), and do not increase data access time (access is similar to the base table).

Multiple choice technology embedded technologies
  1. log entry is written to the system log

  2. log entry is written to trace & error log

  3. log entry is written to availability log

  4. Log entry is written to system log, trace & error log and availability log.

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

When a PMD (Program Module Dump) is generated after a system restart, the system automatically writes a log entry to the Trace & Error log to document this event. This log serves as the primary diagnostic record for system anomalies and restarts. The entry is not written to the system log or availability log - only the Trace & Error log captures PMD-related information.

Multiple choice technology web technology
  1. SQL cache invalidation

  2. Trigger

  3. GridView

  4. Refresh

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

SQL Cache Invalidation is a feature that automatically removes cached data when the underlying database data changes. This solves the problem of stale cached data by providing real-time cache updates based on database triggers, eliminating the need for fixed time-based refresh intervals.

Multiple choice technology web technology
  1. SQL server 2005

  2. MS Access

  3. MS Excel

  4. SQL Server Express

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

ASP.NET 2.0's membership and roles system stores user authentication and authorization data in SQL Server Express by default. This provides a free, embedded database option for user management without requiring a full SQL Server license.