WorksheetsPage 1
Total questions: 12
Worksheet time: 6mins
Which of the following is an advantage of DBMS over File System?
Data redundancy increases
Better data integrity and security
No need for backup
Data becomes unstructured
In a file system, the major problem is:
Data consistency
Data redundancy and duplication
Centralized control
Security enforcement
Which data model organizes data in a tree-like structure?
Relational model
Network model
Hierarchical model
Object model
Which data model supports many-to-many relationships directly?
Hierarchical model
Network model
Relational model
In the relational model, data is stored in the form of:
Graphs
Trees
Tables
Objects
The three-level architecture of DBMS includes:
User, System, Hardware
External, Conceptual, Internal
Logical, Physical, Network
Client, Server, Database
Physical data independence refers to:
Changing schema without changing programs
Changing storage without affecting conceptual schema
Changing user interface
Deleting tables
Logical data independence refers to:
Changing physical storage only
Changing hardware configuration
Changing conceptual schema without affecting external views
An entity in ER model represents?
Relationship between tables
Real-world object or concept
Attribute of a table
Key field
Which key uniquely identifies each record in a relation?
Foreign key
Composite key
Primary key
Alternate key
Specialization in EER model is:
Combining entities
Dividing a super class into sub classes
Removing attributes
Mapping relations
During ER-to-Relational mapping, a many-to-many relationship is converted into:
One table only
Two tables only
Separate relation with foreign keys
