Dear students, Welcome to my post on Class 12 IT ITeS Domestic CRM Voice Session 1 RDBMS Concepts Questions Answers. Here I have provided the exercise as well as additional questions answers of Session 1 RDBMS Concepts from Class 12 Domestic CRM Voice book published by PSSCIVE.
Class 12 IT ITeS Domestic CRM Voice Session 1 RDBMS Concepts Questions Answers
Check your Progress
A. Multiple Choice Questions
- A database is a
(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
Ans : (c) Organized collection of data or information that can be accessed, updated and managed
2. Which of the following is not a valid SQL type ?
(a) float
(b) numeric
(c) decimal
(d) character
Ans: (c) decimal
3. In DBMS, table is known as _______ and row is known as ________.
(a) relation, tuple
(b) tuple, tuple
(c) tuple, relation
(d) relation, relation
Ans: (a) relation, tuple
4. In any table, the data types describe the kind of _________ that it can contain.
(a) table
(b) data
(c) number
(d) column
Ans: (b) data
5. The SQL statement used to select data items from the database is
(a) SELECT
(b) USE
(c) ALTER
(d) CREATE
Ans: (a) SELECT
6. The database can be renamed using _________ SQL statement
(a) CREATE DATABASE
(b) RENAME DATABASE
(c) DROP DATABASE
(d) SELECT DATABASE
Ans: (b) RENAME DATABASE
7. The syntax used to show all databases is
(a) USE DATABASES
(b) SELECT DATABASES
(c) SHOW DATABASES
(d) DISPLAY DATABASE
Ans: (c) SHOW DATABASES
8. In a database table the field which uniquely identifies each row in the table is known as ________
(a) primary key
(b) unique key
(c) composite key
(d) foreign key
Ans: (a) primary key
9. Foreign key is a ___________ key in another table.
(a) primary
(b) unique
(c) composite
(d) candidate key
Ans : (a) primary
10. The multiple columns that are used as primary key is known as
(a) unique key
(b) composite key
(c) foreign key
(d) candidate key
Ans: (b) composite key
11. Which of the following key is used to link between two tables
(a) primary
(b) foreign
(c) composite
(d) unique
Ans: (b) foreign
12. A primary key cannot be
(a) Zero
(b) foreign key
(c) duplicate
(d) NULL
Ans: (d) NULL
B. Fill in the blanks
- In DBMS, table is known as __________ and row is known as _________.
Ans: relation, tuple or record
2. Organized collection of data or information for accessing, updating and management is known as __________.
Ans: Database
3. A relational database consists of a collection of _________.
Ans: tables.
4. To see all available databases in MySQL ; ________ command is used.
Ans: show databases
5. Data Definition language is the language which is used to defining the ________ of relation.
Ans: design
6. In order to build a link between two tables, ___________ is used.
Ans: foreign key
7. In order to make multiple columns as a Primary Key, ________ can be used.
Ans: Composite Primary Key
8. Foreign key is a field in a table that is __________ in another table.
Ans: Primary Key
9. A Key which uniquely identifies each row in the table is known as __________
Ans: Primary Key
10. A foreign key can be _________ or ____________ _. (null, duplicate)
Ans: null, zero
C. State whether true or False
- DBMS is an interface between Database application and database. Ans: False
- Using the SQL statement RENAME DATABASE; a database can be renamed. Ans: True
- To see all existing databases; SHOW DATABASES; syntax is used. Ans : True
- A Primary Key is basically a Column or Columns. Ans: True
- To make a link between two tables, we can use foreign key constraints. Ans: True
- A Primary Key can be NULL. Ans: False
- A Foreign Key cannot be Duplicate. Ans: True
- If multiple columns are used as Primary Key, it is known as Composite Key. Ans: True
- There could be two Primary keys constraints in a single table. Ans: False
- A Foreign Key cannot have NULL value. Ans: True
D. Short answer questions.
- What is file system? Write down limitations of file system.
Ans: A file system is a method that an operating system uses to control how data is stored, organized, retrieved, and managed on a storage device like a hard disk, SSD, or USB drive. It provides a way to separate data into files and directories and allows users and programs to read, write, modify, and delete files.
Some limitations of file system are –
i. Difficulty in Access : In file system there is no mechanism to retrieve data. Data maintained in a file system are accessed through application programs. So, sometimes it is difficult to access data in the required format.
ii. No Multi- User Support : Basic file systems are not designed for environments where multiple users or applications need simultaneous access with permissions.
iii. Data Redundancy and inconsistency : Redundancy means same data are duplicated in different files. There is no built-in mechanism to avoid duplication of data in a file system. Redundancy leads to excess storage use and may cause data inconsistency also.
iv. Data Dependency : Data are stored in a specific format or structure in a file. If the structure or format itself is changed, all the existing application programs accessing that file also need to be changed.
2. Why foreign keys are allowed to have NULL values? Explain with an example.
Ans: Foreign keys can have NULL values to allow flexibility in representing optional relationships. A NULL in a foreign key column means that the relationship is not currently defined or not applicable.
3. What are the limitations of file system and how that are overcome by DBMS ?
Ans:
4. What is database schema?
Ans:
5. What is data redundancy and its associated problems?
Ans:
6. How data redundancy problem is solved in DBMS?
Ans:
7. What is MYSQL and its features?
Ans:
8. What are various data types available in MYSQL?
Ans:
9. Differentiate between: (a) Database state and database schema (b) Primary key and foreign key (c) Degree and cardinality of a relation
Ans:
10. Explain the terms (a) Relation (b) Domain (c) Tuple (d) Attribute (e) Degree (f) Cardinality (g) Primary Key (h) Foreign Key
Ans:
11. Describe the various integrity constraints?
Ans:
Hello students,
Welcome to my site www.elearnersmentor.com. I have been in teaching profession since 2004. Presently I am working as a vocational subject teacher(IT) in a reputed govt. higher secondary school. Read more