W3. SQL Or

Question 1

Q: What does the SQL OR operator do?

Answer 1

A: It filters records based on multiple conditions, returning records if at least one condition is true.

Question 2

Q: Write a SQL query to select all customers from Germany or Spain.

Answer 2

SELECT * FROM Customers 
WHERE Country = 'Germany' OR Country = 'Spain';

Question 3

Q: What is the syntax for using multiple OR conditions in SQL?

Answer 3

SELECT column1, column2, …
FROM table_name
WHERE condition1 OR condition2 OR condition3 …;

Question 4

Q: How does the OR operator differ from the AND operator?

Answer 4

A: OR requires at least one condition to be true, while AND requires all conditions to be true.

Question 5

Q: Write a query to select all customers where the city is “Berlin,” the CustomerName starts with “G,” or the country is “Norway.”

Answer 5

SELECT * FROM Customers 
WHERE City = 'Berlin' OR CustomerName LIKE 'G%' OR Country = 'Norway';

Question 6

Q: Can AND and OR operators be combined in the same SQL query?

Answer 6

A: Yes, they can be combined, often using parentheses for correct grouping.

Question 7

Q: Why are parentheses important when using AND and OR together?

Answer 7

A: They ensure the intended grouping of conditions, so SQL evaluates them in the correct order.

Question 8

Q: Write a query to select all Spanish customers with names starting with “G” or “R.”

Answer 8

SELECT * FROM Customers 
WHERE Country = 'Spain' AND (CustomerName LIKE 'G%' OR CustomerName LIKE 'R%');

Question 9

Q: What can happen if parentheses are omitted in a combined AND/OR query?

Answer 9

A: SQL may misinterpret the grouping, returning unintended results.

Question 10

Q: Write a query to select customers who are either from Spain and start with “G” or start with “R” regardless of country.

Answer 10

SELECT * FROM Customers 
WHERE Country = 'Spain' AND CustomerName LIKE 'G%' OR CustomerName LIKE 'R%';