1.What is a database?
a) Organized collection of information that cannot be accessed, updated, and managed
b) Collection of data or information without organizing
c) Organized collection of data or information that can be accessed, updated, and managed
d) Organized collection of data that cannot be updated

 

2.What is DBMS?
a) DBMS is a collection of queries
b) DBMS is a high-level language
c) DBMS is a programming language
d) DBMS stores, modifies and retrieves data

 

3.Who created the first DBMS?
a) Edgar Frank Codd
b) Charles Bachman
c) Charles Babbage
d) Sharon B. Codd

 

4.Which type of data can be stored in the database?
a) Image oriented data
b) Text, files containing data
c) Data in the form of audio or video
d) All of the above

 

 

5.Which of the following is not a type of database?
a) Hierarchical
b) Network
c) Distributed
d) Decentralized

 

6.Which of the following is not an example of DBMS?
a) MySQL
b) Microsoft Acess
c) IBM DB2
d) Google

 

7.Which of the following is a feature of DBMS?
a) Minimum Duplication and Redundancy of Data
b) High Level of Security
c) Single-user Access only
d) Support ACID Property

 

8.Which of the following is known as a set of entities of the same type that share same properties, or attributes?
a) Relation set
b) Tuples
c) Entity set
d) Entity Relation model

 

9.What is information about data called?
a) Hyper data
b) Tera data
c) Meta data
d) Relations

 

10.What does an RDBMS consist of?
a) Collection of Records
b) Collection of Keys
c) Collection of Tables
d) Collection of Fields

 

 11.The values appearing in given attributes of any tuple in the referencing relation must likewise occur in specified attributes of at least one tuple in the referenced relation, according to _____________________ integrity constraint.
a) Referential
b) Primary
c) Referencing
d) Specific

 

 

12._____________ is a hardware component that is most important for the operation of a database management system.
a) Microphone
b) High speed, large capacity disk to store data
c) High-resolution video display
d) Printer

 

 

13.The DBMS acts as an interface between ________________ and ________________ of an enterprise-class system.
a) Data and the DBMS
b) Application and SQL
c) Database application and the database
d) The user and the software

 

14.______________ is a set of one or more attributes taken collectively to uniquely identify a record.
a) Primary Key
b) Foreign key
c) Super key
d) Candidate key

 

15.Which of the following set should be associated with weak entity set for weak entity to be meaningful?
a) Neighbour set
b) Strong entity set
c) Owner set
d) Identifying set

 

16.Which forms have a relation that contains information about a single entity?
a) 4NF
b) 2NF
c) 5NF
d) 3NF

 

17.The top level of the hierarchy consists of ______ each of which can contain _____.
a) Schemas, Catalogs
b) Schemas, Environment
c) Environment, Schemas
d) Catalogs, Schemas

 

18._______ indicates the maximum number of entities that can be involved in a relationship.
a) Greater Entity Count
b) Minimum cardinality
c) Maximum cardinality
d) ERD

 

19.The user IDs can be added or removed using which of the following fixed roles?
a) db_sysadmin
b) db_accessadmin
c) db_securityadmin
d) db_setupadmin

 

 

20.Why the following statement is erroneous?

SELECTdept_name, ID,avg(salary)

FROM instructor

GROUPBYdept_name;

1. a) Dept_id should not be used in group by clause
   b) Group by clause is not valid in this query
   c) Avg(salary) should not be selected
   d) None

 

21.Which of the following is not the utility of DBMS?
i) Backup ii) Loading iii) Process Organization iv) File organization
a) i, ii, and iv only
b) i, ii and iii only
c) i, iii and iv only
d) All i, ii, iii, and iv

 

22.What is the function of the following command?

Delete from r where P;

1. a) Clears entries from relation
   b) Deletes relation
   c) Deletes particular tuple from relation
   d) All of the mentioned

 

23.Which of the following is popular for applications such as storage of log files in a database management system since it offers the best write performance?
a) RAID level 0
b) RAID level 1
c) RAID level 2
d) RAID level 3

 

24.Which of the following represents a query in the tuple relational calculus?
a) { }{P(t) | t }
b) {t | P(t)}
c) t | P() | t
d) All of the mentioned

 

 

25.Evaluate the statements issued by the DBA in the given sequence if OE and SCOTT are the users and the ORDERS table is owned by OE.

CREATEROLE r1;GRANTSELECT,INSERTONoe. orders TO r1;GRANT r1 TOscott;GRANTSELECTONoe. orders TOscott;REVOKESELECTONoe.ordersFROMscott;

What would be the outcome after executing the statements?
a) The REVOKE statement would give an error because the SELECT privilege has been granted to the role R1
b) The REVOKE statement would remove the SELECT privilege from SCOTT as well as from the role R1
c) SCOTT would be able to query the OE.ORDERS table
d) SCOTT would not be able to query the OE.ORDERS table

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In Prim’s, you always keep a connected component, starting with a single vertex. You look at all edges from the current component to other vertices and find the smallest among them. You then add the neighbouring vertex to the component, increasing its size by 1. In N-1 steps, every vertex would be merged to the current one if we have a connected graph.

In Kruskal’s, you do not keep one connected component but a forest. At each stage, you look at the globally smallest edge that does not create a cycle in the current forest. Such an edge has to necessarily merge two trees in the current forest into one. Since you start with N single-vertex trees, in N-1 steps, they would all have merged into one if the graph was connected.

 

Use Prim’s algorithm when you have a graph with lots of edges.

For a graph with V vertices E edges, Kruskal’s algorithm runs in O(E log V) time and Prim’s algorithm can run in O(E + V log V) amortized time, if you use a Fibonacci Heap.

Prim’s algorithm is significantly faster in the limit when you’ve got a really dense graph with many more edges than vertices. Kruskal performs better in typical situations (sparse graphs) because it uses simpler data structures.

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If we talk about Optimality:

In the Greedy method approach, there is no guarantee of getting the optimal solution, Generally, it gives the optimal local solution.

while

In the dynamic approach, there is a guarantee of getting an optimal solution as it considers all the cases as long to get optimal. It gives optimal global solutions.

 

For example, let’s say that you have to get from point A to point B as fast as possible, in a given city, during rush hour. A dynamic programming algorithm will look into the entire traffic report, looking into all possible combinations of roads you might take, and will only then tell you which way is the fastest. Of course, you might have to wait for a while until the algorithm finishes, and only then can you start driving. The path you will take will be the fastest one (assuming that nothing changed in the external environment).

On the other hand, a greedy algorithm will start you driving immediately and will pick the road that looks the fastest at every intersection. As you can imagine, this strategy might not lead to the fastest arrival time, since you might take some “easy” streets and then find yourself hopelessly stuck in a traffic jam.

 

 

 

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