SQL Data Manipulation: Master Insert, Update, and Delete Operations

Question 1

Which SQL statement is used to delete all data from the 'Customer' table?

Accepted Answer

DELETE * FROM Customer

Answer

REMOVE FROM Customer

Answer

DELETE ALL FROM Customer

Answer

DROP TABLE Customer

Question 2

In SQL, what's the key difference between the INSERT and UPDATE statements?

Accepted Answer

INSERT adds new table rows, while UPDATE modifies existing ones.

Answer

UPDATE adds new table rows, while INSERT modifies existing ones.

Answer

Both INSERT and UPDATE can add new table rows.

Answer

Both INSERT and UPDATE can modify existing table rows.

Question 3

In SQL, which keyword is used to modify existing data in a database table?

Accepted Answer

UPDATE

Answer

ALTER

Answer

DELETE

Answer

INSERT

Question 4

To add a new row to a table in SQL, which DML statement is used?

Accepted Answer

INSERT

Answer

ALTER

Answer

UPDATE

Answer

DELETE

Question 5

In SQL, which keyword is used to remove data from a database table?

Accepted Answer

DELETE

Answer

ALTER

Answer

UPDATE

Answer

INSERT

Question 6

Which clause within a SQL UPDATE statement specifies the rows to be modified?

Accepted Answer

WHERE

Answer

SET

Answer

FROM

Answer

ORDER BY

Question 7

Within a SQL INSERT statement, which clause is used to specify the values to be added?

Accepted Answer

VALUES

Answer

WHERE

Answer

SET

Answer

ORDER BY

Question 8

In SQL, which keyword is used to establish a new table?

Accepted Answer

CREATE

Answer

ALTER

Answer

DELETE

Answer

INSERT

Question 9

Which SQL data type is used to store dates?

Accepted Answer

DATE

Answer

INT

Answer

VARCHAR

Answer

FLOAT

Question 10

Within SQL, which function is used to convert a string to uppercase?

Accepted Answer

UPPER()

Answer

LOWER()

Answer

TRIM()

Answer

SUBSTR()

Question 11

Which operator in SQL is used to join two strings?

Accepted Answer

||

Answer

+

Answer

*

Answer

/

Question 12

Within SQL, which keyword is used to group rows by a specified column?

Accepted Answer

GROUP BY

Answer

ORDER BY

Answer

WHERE

Answer

HAVING

Question 13

Which DML statement is used to add a new row to a table?

Accepted Answer

INSERT INTO

Answer

CREATE TABLE

Answer

UPDATE

Answer

DELETE FROM

Question 14

What is the correct syntax to update a specific row in a table?

Accepted Answer

UPDATE table_name SET column1 = value1 WHERE condition;

Answer

UPDATE table_name WHERE condition SET column1 = value1;

Answer

SET UPDATE table_name SET column1 = value1 WHERE condition;

Answer

UPDATE SET table_name column1 = value1 WHERE condition;

Question 15

What is the purpose of a PRIMARY KEY constraint?

Accepted Answer

To ensure that each row in a table has a unique identifier

Answer

To prevent duplicate rows from being inserted

Answer

To enforce data integrity by referencing other tables

Answer

To optimize query performance

Question 16

What is the purpose of a foreign key constraint?

Accepted Answer

To link rows in different tables and enforce referential integrity

Answer

To prevent duplicate values in a table

Answer

To create a relationship between two tables

Answer

To optimize query performance

Question 17

Which of the following is a DML statement that can be used to retrieve data from a table?

Accepted Answer

SELECT

Answer

INSERT

Answer

UPDATE

Answer

DELETE

Question 18

Which syntax is correct for updating the 'last_name' of the employee with 'id' 3 to 'Jones' using an UPDATE statement?

Accepted Answer

UPDATE employees SET last_name = 'Jones' WHERE id = 3

Answer

UPDATE employees SET 'last_name' = 'Jones' WHERE 'id' = 3

Answer

UPDATE employees last_name = 'Jones' WHERE id = 3

Question 19

To insert new data into a SQL table, which statement is used?

Accepted Answer

INSERT

Answer

SELECT

Answer

UPDATE

Answer

DELETE

Question 20

What is the correct syntax for the `INSERT` statement?

Accepted Answer

INSERT INTO table_name (column1, column2, ...) VALUES (value1, value2, ...)

Answer

INSERT table_name (column1, column2, ...) SET value1, value2, ...

Answer

INSERT INTO table_name SET column1 = value1, column2 = value2, ...

Answer

INSERT table_name VALUES (value1, value2, ...)

Question 21

In an `UPDATE` statement, what is the purpose of the `WHERE` clause?

Accepted Answer

To identify the rows that should be updated

Answer

To specify the new values for the updated rows

Answer

To create a new table with the updated data

Answer

To delete rows from the table

Question 22

Explain the difference between a primary key and a foreign key.

Accepted Answer

A primary key is unique for each row, while a foreign key references the primary key in another table

Answer

A foreign key is unique for each row, while a primary key references the foreign key in another table

Answer

Primary and foreign keys are the same thing

Answer

There is no difference between a primary key and a foreign key

Question 23

Which SQL statement is used to erase data from a table?

Accepted Answer

DELETE

Answer

SELECT

Answer

INSERT

Answer

UPDATE

Question 24

What is the syntax for the `DELETE` statement?

Accepted Answer

DELETE FROM table_name WHERE condition

Answer

DELETE table_name SET condition

Answer

DELETE FROM table_name

Answer

DELETE table_name (column1, column2, ...)

Question 25

What advantage does using DML in SQL offer?

Accepted Answer

Efficient data manipulation

Answer

Enhanced data security and integrity

Answer

Simplified database design

Answer

Improved database performance

Question 26

What is the role of a transaction in SQL?

Accepted Answer

To ensure data consistency and integrity during multiple operations

Answer

To accelerate database operations

Answer

To create a database backup

Answer

To erase data from a database

Question 27

What is the correct syntax to insert a new row into the 'Customers' table with columns 'CustomerID', 'CustomerName', and 'ContactNumber'?

Accepted Answer

INSERT INTO Customers(CustomerID, CustomerName, ContactNumber) VALUES (101, 'John Doe', '0123456789')

Answer

ADD ROW INTO Customers(CustomerID, CustomerName, ContactNumber) VALUES (101, 'John Doe', '0123456789')

Answer

INSERT Customers SET CustomerID = 101, CustomerName = 'John Doe', ContactNumber = '0123456789'

Answer

INSERT Customers WITH CustomerID = 101, CustomerName = 'John Doe', ContactNumber = '0123456789'

Question 28

Which error is most likely encountered when attempting to use a DML statement to modify data in a non-existent table?

Accepted Answer

Table not found error

Answer

Syntax error

Answer

Data type mismatch error

Answer

Foreign key constraint error

Question 29

Which Data Manipulation Language (DML) statement is used to add new data to a table?

Accepted Answer

INSERT

Answer

SELECT

Answer

UPDATE

Answer

DELETE

Question 30

What is the correct syntax for inserting a new row into the 'customers' table with values for 'name', 'address', and 'phone_number'?

Accepted Answer

INSERT INTO customers (name, address, phone_number) VALUES ('John Doe', '123 Main Street', '555-1212')

Answer

INSERT customers (name, address, phone_number) VALUES ('John Doe', '123 Main Street', '555-1212')

Answer

INSERT customers (name, address) VALUES ('John Doe', '123 Main Street')

Answer

INSERT customers NAME ('John Doe'), ADDRESS ('123 Main Street'), PHONE_NUMBER ('555-1212')

Question 31

Which clause is used to specify the condition for updating rows in a table using an UPDATE statement?

Accepted Answer

WHERE

Answer

SET

Answer

FROM

Answer

ORDER BY

Question 32

What is the purpose of using the 'LIMIT' clause in an UPDATE statement?

Accepted Answer

To restrict the number of rows that are updated

Answer

To specify the order in which rows are updated

Answer

To filter rows that are updated based on a condition

Answer

To group rows that are updated based on column values

Question 33

Which DML statement is used to remove rows from a table?

Accepted Answer

DELETE

Answer

INSERT

Answer

UPDATE

Answer

SELECT

Question 34

What is a key benefit of using transactions when performing DML operations?

Accepted Answer

Transactions ensure that changes to the database are either fully committed or rolled back

Answer

Transactions improve the performance of DML operations

Answer

Transactions prevent data loss in case of system failure

Answer

Transactions allow multiple users to access the database concurrently

Question 35

How do triggers help ensure data integrity when using DML commands in a database?

Accepted Answer

By enforcing predefined rules when data is modified.

Answer

By preventing unauthorized access to sensitive data.

Question 36

In which scenario would employing a subquery within a DML statement be beneficial?

Accepted Answer

Updating multiple rows based on a condition derived from another table

Answer

Inserting data from one table into another

Answer

Deleting rows based on a specified range of values

Question 37

Which of the following is not a Data Manipulation Language (DML) statement in SQL?

Accepted Answer

SELECT * FROM

Answer

INSERT INTO

Answer

UPDATE SET

Answer

DELETE FROM

Question 38

How does the WHERE clause function differently in SQL SELECT and UPDATE statements?

Accepted Answer

In SELECT, it filters retrieved rows; in UPDATE, it identifies rows to modify.

Answer

Both SELECT and UPDATE use WHERE to specify affected columns.

Answer

WHERE is not used in UPDATE statements.

Answer

In SELECT, WHERE modifies data; in UPDATE, it cannot retrieve data.

Question 39

To delete a record from the 'customers' table where the primary key 'id' has a value of 5, which SQL syntax is correct?

Accepted Answer

DELETE FROM customers WHERE id = 5

Answer

DELETE customers WHERE id = 5

Answer

REMOVE FROM customers WHERE id = 5

Answer

DELETE * FROM customers WHERE id = 5

Question 40

How can Data Manipulation Language (DML) statements be used in data management?

Accepted Answer

Updating customer details in an online shopping system

Answer

Creating reports from a database

Answer

Creating a new database

Question 41

Which DML statement is used to remove a row from a table?

Accepted Answer

DELETE

Answer

INSERT

Answer

UPDATE

Answer

SELECT

Question 42

What is the correct syntax to insert a new row into a table named 'Customers' with columns 'ID', 'Name', and 'Email'?

Accepted Answer

INSERT INTO Customers (ID, Name, Email) VALUES (1, 'John Doe', 'john.doe@example.com')

Answer

UPDATE Customers SET Name = 'John Doe', Email = 'john.doe@example.com' WHERE ID = 1

Answer

DELETE FROM Customers WHERE ID = 1

Answer

SELECT * FROM Customers WHERE Name = 'John Doe'

Question 43

Which operator is used to compare values in an UPDATE statement?

Accepted Answer

=

Answer

!=

Answer

>

Answer

<

Question 44

What is the primary purpose of using the WHERE clause in a DML statement?

Accepted Answer

To specify which rows will be affected by the statement

Answer

To create a new table

Answer

To sort the results of the statement

Answer

To group the results of the statement

Question 45

Which DML statement is utilized to retrieve information from a table?

Accepted Answer

SELECT

Answer

INSERT

Answer

UPDATE

Answer

DELETE

Question 46

What is the key distinction between a primary key and a foreign key?

Accepted Answer

A primary key uniquely identifies each row in a table, while a foreign key references the primary key of another table.

Answer

A foreign key uniquely identifies each row in a table, while a primary key references the foreign key of another table.

Answer

Both primary keys and foreign keys uniquely identify each row in a table.

Answer

There is no distinction between a primary key and a foreign key.

Question 47

Which data type should be used in a SQL database to store a date?

Accepted Answer

DATE

Answer

INT

Answer

FLOAT

Answer

VARCHAR

Question 48

What is the intended use of transactions in SQL?

Accepted Answer

To ensure a set of operations is executed as a single unit of work

Answer

To create a backup of the database

Answer

To enhance query performance

Answer

To prevent data loss

Question 49

Which SQL statement is used to establish a new table?

Accepted Answer

CREATE TABLE

Answer

INSERT INTO

Answer

UPDATE

Answer

DELETE

Question 50

What is the purpose of utilizing indexes in a SQL database?

Accepted Answer

To enhance query performance

Answer

To guarantee data integrity

Answer

To create a backup of the database

Answer

To prevent data loss