Top 1000+ Database Subject Mcqs Pdf Download Set No 06

251. DML commands are used for

  1. inserting data into databases  
  2. creating database
  3. destroying databases 
  4. creating DB objects .

 252.Structural constraints of a relationship type refer

  1. to  identifying the owner entity type relevant to a given entity type
  2. whether the existence of an entity depends on it being related to another entity via the relationship type. 
  3. role that a participating entity from the entity type plays in each relationship instance

253.Identify the correct statement.

  1. Entity integrity constraints specify that primary key values can be composite.
  2. Entity integrity constraints are specified on individual relations.  
  3. Entity integrity constraints are specified between weak entities .
  4. When entity integrity rules are enforced, a tuple
  5. in one relation that refers to another relation must refer to a n existing tuple. 

254.what is the impact of setting multiple indexes for the same key, in index sequential files ?

  1. Multiple indexes for the same key can not be set
  2. It increases efficiency
  3. It decreases efficiency
  4. It will increase complexity as the access time will be increased 

255. Which of the following is not true regarding Indexes ?

  1. Index can be defined even when there is no data in the table
  2. It support Range selections
  3. It can be created using ‘Create Index’ statement
  4. It can not be created on composite attributes

  1.   

256.While recovering data, which of the following files does a recovery m anger examines at first?

  1. A system file
  2. Log file  
  3. Data dictionary
  4. Metadata

 257. The main memory of a computer system is also known as  ROM

  1. RAM   
  2. PROM
  3. Hard disk

258._______is a control that enables users to select one option from an associated list; users can also type an option.

  1. Combo box  
  2. Button
  3. Text box
  4.   Static area

 259.______ records data by burning microscopic holes in the surface of the disk with a laser.

  1. Hard disk
  2. RAM
  3. Optical disk    
  4. Floppy disk

260.Which of following is NOT generally the aim of data partitioning and placement of data? 

  1. Reduce Workload
  2. Balance Workload
  3. Merging different relations  
  4. Speed up rate of useful works .

261.  ALTER TABLE exams

RENAME COLUMN Q_description

TO Question Description,

Student ID  to  Student ID.

Syntax of ALTER TABLE is NOT correct.

  1. True
  2. False 

 262.Which of the following is true regarding Index? 

  1. Index can only be created for a single table in database
  2. Index can maximum be created for two tables in database
  3. Index should be created for
  4. every table in the database

 Index can be created for every table in the database


263.Which feature of database provides conversion from inconsistent state of DB to a consistent state ensuring minimum data loss ?

  1. User accessible catalog
  2. Data processing
  3. Recovery service  
  4. authorization service

 264.Which of the following statements is true about the views? 

  1. View can not be used for retrieving data
  2. view is always a complete set of all the tables in a database
  3. The results of using a view are not permanently stored in the database.      
  4. Rows can not be updated or deleted in the view 

  1.  

265. Which of the following is true about TRUNCATE?

  1. Can be Rolled back.
  2. Activates Triggers .
  3. DML  is Command.
  4. Resets identity of the table.  l

266.Which of the following will be deleted relating to a table if you use TRUNCATE command?

  1. all rows in a table   
  2. indexes
  3. table structure
  4. tables columns
  5.  constraints

 267.Which of the following is not true about relational tables?

  1. Column values are of the same kind.
  2. Each row is unique.
  3. Each column must have a unique name.
  4. The sequence of rows is significant.  

  1.  

268.Which of the following is not true about De -normalization?

  1. It is the process of attempting to optimize the performance of a database
  2. De-normalization is a technique to move from lower to higher normal forms of database modeling
  3. In de-normalization it is required to add redundant data. 
  4. It enhances the performance of DB

269.Which of the following is the correct way to find out the size of Cartesian product incase of CROSS JOIN? 

  1. the number of columns in the first table multiplied by the number of columns in the
  2. second table.
  3. the number of columns in the first table multiplied by the number of rows in the second table. 
  4. the number of rows in the first table multiplied by the number of columns in the
  5. first table.
  6. the number of rows in the first table multiplied by the number of rows in the second table.  

270.Which of the following is INCORRECT about VIEWS?

  1. It is not possible to left out the data which is not required for a specific view
  2. A database view displays one or more database records on the same page. 
  3. Views can be used as security mechanisms
  4. Views are generally used to focus the perception each user has of the database. 

271.What is the maximum limit of keys in context with Indexed sequential files?  

  1. 1
  2. 9
  3. 235

272 . Structural constraints of a relationship type refer to  identifying the owner entity type relevant to a given entity type

  1. whether the existence of an entity depends on it being related to another entity via the relationship type.  
  2. the role that a participating entity from the entity type plays
  3. in each relationship instance. 
  4. constraints applicable in granting access to tables , columns and views in a database schema.

273.What is the impact of setting multiple indexes for the same key, in index sequential files

  1. Multiple indexes for the same key can not be set
  2. It increases efficiency 
  3. It decreases efficiency
  4. It will increase complexity as the access time will be increased 

274.Which of the given techniques is /are used to improve query performance in database?

  1. Good File organization
  2. Indexing   

275. Both Indexing and Good File organization  Select only one record per query While recovering data, which of the following files does a recovery manager examines at first?

  1. A system file
  2. Data dictionary
  3. Log file  
  4. Metadata

  276._______ is a control that users click to perform an action, set or toggle a state, or set an option.

  1. Button     
  2. Text box
  3. Input form
  4. Report

277._______is a control that enables users to select one option from an associated list; users can also type an option.

  1. Button
  2. Combo box  
  3. Text box
  4. Static area

278.Partitions may become unbalanced in

  1. Range partitioning  
  2. Hash partitioning
  3. List partitioning 
  4. Vertical partitioning

279.Only one type of constraint can be enforced in any table by CREATE command 

  1. True
  2. False  

280.ALTER COLUMN

  1. True
  2. False     

281.which of the following is disadvantage of chaining technique to handle the collisions ? 

  1. Unlimited Number of elements
  2. Fast re-hashing
  3. Overhead of multiple linked lists  
  4. Maximum number of elements must be known 

282 .In which of the following, Materialized Views are suitable 

  1. Data warehousing
  2. Decision support 
  3. Mobile computing
  4. All of the Given    

283. Software package designed to store and manage databases  Database

  1. DBMS   
  2. Data model
  3. Data

284..A super key that does not contain a subset of attributes that is itself a super key is called a ____.

  1. candidate key 
  2. primary key
  3. super key
  4. secondary key

 285.A ____ relationship exists when an association is maintained within a single entity.

  1. unary   
  2. ternary
  3. binary
  4. weak

286.Which of the following is NOT one of the ways of resolving deadlocks ?

  1. It is the cause of deadlock.
  2. A message is passed to the victim and depending on the system the transaction may or may not be
  3. started again automatically.
  4. Picking a list of all previously completed transactions and undoing all the updates.  
  5. Rollback `victim’ transaction and restart it.

287.  You can’t modify more than one table at a time through a view.

  1. True l
  2. False

288.Which of the following is one of the purposes of using DML commands ?

  1. Creating databases
  2. Destroying databases
  3. Inserting data in tables  
  4. None

289.How many clustered index(es ) do each database table have? 

  1. 3
  2. 5
  3. 1  

290.Suppose there are 4 rows and 3 columns in TABLE1 and 6 rows and 5 columns in TABLE2; what is the size of the Cartesian product incase of CROSS JOIN between these two tables?

  1. 24     
  2. 20
  3. 18 

291.Which of the following is not one of the properties of Transaction?

  1. atomicity
  2. consistency
  3. redundancy   
  4. durability

 292.Which of the following is INCORRECT about VIEWS?

  1. It is not possible to left out the data which is not required for a specific view
  2. A database view displays one or more database records on the same page. 
  3. Views can be used as security mechanisms
  4. Views are generally used to focus the perception each user has of the database.

 293.Which of the following gives all the fields from employee table named as EMP?

  1. select * from EMP ; 
  2. select emp* from EMP’
  3. select emp_id where EMP; 
  4. select * where EMP;

  1.  

295.Which of the following types of partitioning reduces the chances of unbalanced partitions ?

  1. vertical
  2. List
  3. Hash 
  4. Range
  5. to a large extent 

296.Which of the following is one of the purposes of using DDL commands ?

  1. inserting records into databases
  2. updating records into databases  manipulating databases
  3. creating and destroying databases 

  1.  

297.Which of the following statements creates a database named COMPANY?

  1. CREATE DATABASE company
  2. CREATE DB company
  3. ADD DATABASE company
  4. CREATE company DATABASE 

  1.  

298.What is the impact of setting multiple indexes for the same key, in index sequential files ? 

  1. Multiple indexes for the same key can not be set
  2. It increases efficiency
  3. It decreases efficiency
  4. It will increase complexity as the access time will be increased

300.Consider a transaction which includes following operations Z= Z + 10 Write Z

Suppose that the value of Z after addition and the execution of this operation is

Now against the write operation the entry made in the log file will be

What does Z reflects in the above entry?

  1. Object being updated   
  2. Identity of the transaction
  3. Object value
  4. Identity of the next transaction to be executed