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WHERE Clause

5 min read Quiz at the end

WHERE filters rows. Use =, !=, <, >, BETWEEN, LIKE, IN, and IS NULL. Never use = NULL — always use IS NULL. Combine conditions with AND and OR and use parentheses to control the evaluation order.

Filtering Rows with WHERE

SELECT * FROM users WHERE age > 25;
SELECT * FROM users WHERE name = 'Alice';
SELECT * FROM users WHERE age BETWEEN 20 AND 30;
SELECT * FROM users WHERE name LIKE 'A%';
SELECT * FROM users WHERE age IN (25, 30, 35);
SELECT * FROM users WHERE email IS NOT NULL;
SELECT * FROM users WHERE age > 20 AND name LIKE 'B%';

← SELECT Queries Next: ORDER BY and LIMIT →

Topic Quiz · 5 questions

Test your understanding before moving on

1. Which operator checks a range?

💡 Wait — BETWEEN checks a range: WHERE age BETWEEN 20 AND 30.

2. Which operator matches a pattern?

💡 LIKE with % wildcard matches text patterns.

3. How do you check for NULL values?

💡 Use IS NULL or IS NOT NULL — never = NULL.

4. Which operator checks multiple values?

💡 IN checks if a value is in a list: WHERE age IN (25, 30, 35).

5. Which keyword inverts a condition?

💡 NOT inverts a condition: NOT IN, NOT LIKE, NOT BETWEEN.

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WHERE Clause

Filtering Rows with WHERE

Test your understanding before moving on