[Basic Grammar] SQL AND Operator

The WHERE Clause can contain one or many AND Operators. It is usd to filter records based on more than one condition. AND and OR Operators are like values(conditions) that the questions asks for. 

 

Example 

Select all customers from Spain that starts with the letter 'G': 

SELECT * fROM Customers
WHERE COUNTRY = 'Spain' AND CustomerName LIKE 'G%';

• Syntax 

SELECT column1, column2, ...
FROM table_name
WHERE condition1 AND condition2 AND condition3 ...;

 

• All Conditions Must be True 

Example 

SELECT * FROM Customers 
WHERE Country = 'South Korea'
AND City = 'Seoul'
AND PostalCode < 12000;

 

• Combining AND and OR 

We can combine AND and OR operators in WHERE Clause. 

 

Example 

Select all Korean customers that starts with either "H" or "R":

SELECT * FROM Customers 
WHERE Country = 'South Korea' AND CustomerName LIKE 'H%' OR CustomerName LIKE 'R%');

 

 

Without parenthesis, the select statement will return all the customers that start with G and R, regardless of the country value: 

Example 

Select all customers that either: are from Spain and starts with either "G" or "R": 

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

 

Exercises 

1. Retrieve all orders where the "ProductID" is 101 and the "Quantity" is 5.

SELECT* FROM Orders 
WHERE ProductID  = 101 AND Qunatity = 5;

 

2. Fetch all customers with the "Country" column set to 'France' and the "Region" column set to 'Provence-Alpes-Côte d'Azur.'

SELECT * FROM Customers 
WHERE Country = 'France' AND Region = 'Provence-Alpes-Côte d'Azur';

3. Retrieve all products from the "Products" table that have a price less than $50 and are in the "Electronics" category.

SELECT * FROM Products
WHERE Price < 50 AND Category = 'Electronics';