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Ans. 1. ii 2. iv 3. iii 4. i 5. iii 6. iv 7. iv 8. iii 9. ii 10. iii
11. i 12. iii 13. i
B. Fill in the blanks.
1. ................................ is a collection of raw facts and figures, that is processed to produce meaningful information.
2. ................................ refers to a package that enables the users to store, modify and properly maintain the database and that
helps to extract useful information from the database as and when required.
3. The ................................ determines the requirements of the end-users and then develops specifications to meet these
requirements.
4. The concept of a relational database was developed by ................................ .
5. The data type of values in each column is called the ................................ .
6. A ................................ is an attribute or set of attributes that uniquely identifies a row.
7. The ................................ statement allows you to add, modify, and delete columns from an existing table.
8. ................................ command is used to modify the existing records in a table.
9. The ................................ keyword selects all rows from both the tables as long as the condition is satisfied.
10. RIGHT JOIN is also known as ................................ .
Ans. 1. Data 2. DBMS 3. System Analyst 4. E.F. Codd 5. Domain
6. Candidate key 7. ALTER TABLE 8. UPDATE 9. INNER JOIN
10. RIGHT OUTER JOIN
Section B
(Subjective Type Questions)
A. Short answer type questions.
1. What is a database?
Ans. A database is an assembled group of data that enables easy and efficient storage, access, modification, and retrieval of data,
regardless of the amount of data being manipulated. It is a logically coherent, organized collection of related data. Related
data refers to the collection of data, which is stored based on the same context.
2. What do you mean by cardinality?
Ans. It refers to the uniqueness of data values contained in a particular column of a database table.
3. What is Entity Integrity Constraint?
Ans. This constraint specifies that the primary key of a relation cannot have a NULL value. The reason behind this constraint is
that we know the primary key contains no duplicates. However, if we allow null values for a primary key then there can be
multiple tuples for which the primary key is having null values. This would imply that we are allowing duplicate values (NULL)
for a primary key which itself violates the definition of the primary key.
4. What is SQL?
Ans. SQL is a high-level interactive language that allows users to specify what is required to be done in the form of queries. Unlike
other high-level languages, we do not need to specify how the SQL operations are implemented. The database software
which uses SQL is MYSQL.
5. What is INNER JOIN?
Ans. The INNER JOIN keyword selects all rows from both the tables as long as the condition is satisfied. This keyword will create
the result-set by combining all rows from both the tables where the condition satisfies, i.e., value of the common field will
be the same.
6. While entering the data in the table, Seema is not able to leave the column age as blank in the table. What can be the
possible reason? [CBSE Sample Paper 2023]
Ans. NOT NULL constraint in age column
Database Concepts—RDBMS Tool 181

