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1. What does SQL stand for?
a) Structured Query Language
b) Sequential Query Logic
c) Structured Query Language
d) Simple Query Logic
SQL stands for Structured Query Language, which is used to manage and
manipulate relational databases.
2. Which of the following is a primary key characteristic?
a) It can be duplicated
b) It can contain NULL values
c) It uniquely identifies each record
d) It can reference foreign keys
A primary key must contain unique values and cannot be NULL, ensuring
each record is uniquely identified.
3. What is the purpose of a foreign key?
a) To delete data
b) To store binary files
c) To establish a relationship between tables
, d) To create a new database
A foreign key links one table to another, enforcing referential integrity
between related records.
4. Which SQL clause is used to filter results?
a) SELECT
b) FROM
c) WHERE
d) ORDER BY
The WHERE clause is used to filter rows based on specific conditions.
5. Which command is used to retrieve data from a database?
a) SELECT
b) UPDATE
c) DELETE
d) INSERT
SELECT is the SQL command used to query and retrieve data from tables.
6. A database schema is:
a) A type of query
b) The structure of a database
c) A single table
d) An encryption method
A schema defines how data is organized and how relationships among data
are associated.
7. What type of join returns all records from both tables when there is a
match?
, a) LEFT JOIN
b) RIGHT JOIN
c) INNER JOIN
d) OUTER JOIN
An INNER JOIN returns only matching rows from both tables.
8. Which command will add a new record into a table?
a) UPDATE
b) SELECT
c) INSERT INTO
d) DROP
INSERT INTO is used to add new rows into a table.
9. What is normalization?
a) A form of backup
b) Organizing data to reduce redundancy
c) Creating views
d) Encrypting tables
Normalization is a process to efficiently organize data in a database and
eliminate redundancy.
10.What is a NULL value in SQL?
a) Zero
b) Empty string
c) Unknown or missing value
d) Default number
NULL represents missing or unknown data in SQL.