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 programming languages

You develop a Windows-Based application that accesses a Microsoft SQL Server database named ABC. Users must supply a user name and password when they start the application. This information is then used to dynamically build a connection string. When you test the application, you discover that it is not using the SqlClient connection pooling feature. You must reduce the time needed to retrieve information. How should you modify the connection string?

  1. to use the Windows user logon when connection to the TestKing1 database.

  2. to use the SQL Server used login when connection to the TestKing1 database.

  3. to use the same application logon ID and password for every connection to the TestKing1 database.

  4. to use the guest login ID and password for every connection to the TestKing1 database.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Connection pooling in ADO.NET relies on exact string matching. If every user has a unique connection string (different credentials), a new pool is created for each, defeating the purpose. Using a single service account enables pool reuse.

Multiple choice technology programming languages

You develop a Windows-based application ABCApp by using Visual Studio .NET. ABCApp uses a SqlConnection object for database access. You typically run ABCApp on a computer that has limited RAM and hard disk space. After the code finishes using the SqlConnection object, you must ensure that the connection is closed and that any resources consumed by the object are released immediately. What should you do?

  1. Call the Finalize method of the SqlConnection object.

  2. Call the Dispose method of the SqlConnection object.

  3. Set the SqlConnection object equal to Nothing.

  4. Set the SqlConnection object equal to “”.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The Dispose method is the correct approach to immediately release resources and close the connection. Dispose is deterministic - it frees resources right when called. Finalize is non-deterministic (called by garbage collector eventually), setting to Nothing just removes the reference without closing the connection, and setting to "" is invalid for objects.

Multiple choice technology programming languages

You plan to develop a customer information application CustomABC that uses a Microsoft SQL Server database. CustomABC will be used frequently by a large number of users. Your application code must obtain the fastest possible performance when accessing the database and retrieving large amounts of data. You must accomplish this goal with the minimum amount of code. How should you design CustomABC?

  1. Use classes in the System.Data.OleDb namespace.

  2. Use classes in the System.Data.SqlClient namespace.

  3. Use remoting to connect to the SQL Server computer.

  4. Use interoperability to include legacy COM-based data access components.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The System.Data.SqlClient namespace is specifically optimized for Microsoft SQL Server. It uses the TDS (Tabular Data Stream) protocol directly, providing better performance than the generic OleDb provider.

Multiple choice technology programming languages

Which three are DATETIME data types that can be used when specifying column definitions? ( Choose Three)

  1. TIMESTAMP

  2. INTERVAL MONTH TO DAY

  3. INTERVAL DAY TO SECOND

  4. INTERVAL YEAR TO MONTH

  5. TIMESTAMP WITH DATABASE TIMEZONE
Reveal answer Fill a bubble to check yourself
A,C,D Correct answer
Explanation

TIMESTAMP, INTERVAL DAY TO SECOND, and INTERVAL YEAR TO MONTH are valid Oracle datetime/interval types. 'INTERVAL MONTH TO DAY' is not a valid Oracle type, and 'TIMESTAMP WITH DATABASE TIMEZONE' is also not a standard type name.

Multiple choice technology web technology

5.What is a lookup file?

  1. File containing intermediate data while processing

  2. File containing static dataset which is keyed

  3. File containing daily transaction data

  4. Partitioned file which is non-keyed
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A lookup file contains a static reference dataset that is keyed, allowing you to join with transactional data during processing to enrich or validate records. Common examples include state code mappings, currency conversion tables, or product catalogs that don't change frequently. Unlike intermediate files, lookup files are pre-loaded before processing begins.

Multiple choice technology databases

You have a mission critical database named MCDB1 that you want to configure for automatic failover. You have decided to utilize database mirroring. Which database mirroring operating mode should you use?

  1. High safety mode

  2. Asynchronously

  3. High performance mode

  4. Synchronously

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

High safety mode (also called high safety with automatic failover) is the correct database mirroring operating mode for mission critical databases requiring automatic failover. In this mode, transactions are committed synchronously to both principal and mirror servers before acknowledging success, ensuring zero data loss. High performance mode is asynchronous and doesn't support automatic failover.

Multiple choice technology databases

You have been assigned the task of designing a relational database for a client. The database will be used to store an exact copy of specific XML documents that the client needs to retrieve on a regular basis. The client wants to be able to use an application that they created to enter the documents into the database as well as retrieve them. You are in the process of designing a table for the database. What should you do?

  1. Convert the XML documents to relational data and then store them within the database

  2. Create a table that uses XML as the data type for the column that will store the XML documents.

  3. Nothing. You can not store XML documents within a SQL Server 2005 database

  4. Create a table that uses nvarchar(max) as the data type for the column that will store the XML documents
Reveal answer Fill a bubble to check yourself
D Correct answer
Multiple choice technology databases

You are gathering performance and optimization data for your SQL Server 2005 database. Your company has three custom applications that routinely make use of the database. Each application accesses the database using separate login credentials. You wish to gather information concerning the queries executed by each custom application. To gather this data you decide to create a trace using the SQL Server Profiler. You decide to use one of the predefined SQL Server Profiler templates to define what data should be gathered. Which predefined SQL Server Profiler template would best suit your requirements?

  1. TSQL_Duration

  2. TSQL_Grouped

  3. TSQL_Replay

  4. TSQL_SPs
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The TSQL_Grouped template in SQL Server Profiler groups trace information by the application name and login credentials, making it ideal for analyzing queries executed by specific applications.

Multiple choice technology programming languages

ORA-01403 Means?

  1. No data found

  2. Internal error

  3. TNS:could not resolve service name"

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

ORA-01403 is the Oracle error code returned when a SELECT...INTO statement or implicit cursor finds no rows to fetch. It's the standard 'no data found' exception in PL/SQL, commonly handled with NO_DATA_FOUND exception handlers. Other options represent different errors: ORA-00600 is internal error, ORA-12154 is TNS naming failure.

Multiple choice technology programming languages

ORA-12154 Means?

  1. TNS:name lookup failure"

  2. TNS:could not resolve service name"

  3. TNS:protocol adapter error"

  4. Package error raised with DBMS_SYS_ERROR.RAISE_SYSTEM_ERROR
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

ORA-12154 is 'TNS:could not resolve the service name' - Oracle's TNS listener cannot find the database service name specified in the connect string. This is a TNS (Transparent Network Substrate) naming/configuration error. Option A would be ORA-12154 (name lookup failure is essentially the same), Option C is ORA-12560 (protocol adapter error). The key issue is service name resolution in tnsnames.ora.

Multiple choice technology packaged enterprise solutions

What Session.flush() do ?

  1. the state of that object will be synchronized with the database.

  2. the state of that object will be synchronized with the SessionFactory.

  3. remove state of that object from Session.

  4. remove state of that object from SessionFactory.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Session.flush() synchronizes the in-memory state of persistent objects with the database. It executes SQL statements (INSERT, UPDATE, DELETE) to make the database reflect the changes made to objects in the Hibernate Session, but doesn't commit the transaction - use commit() for that.

Multiple choice technology performance

This phase of Oracle tuning is directed at looking for resource shortages in the db_block_buffers, shared_pool_size and sort_area_size.

  1. Instance Tuning

  2. Object Tuning

  3. SQL Tuning

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

Instance Tuning focuses on optimizing memory parameters like db_block_buffers (data cache), shared_pool_size (library cache), and sort_area_size (memory for sorting operations). These are instance-level resource configurations that affect the entire database instance, not individual objects or SQL statements.