DataPlayArena
SQL Reference Guide
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2. Filtering Data Reference

How to filter rows.

=
Return: Value

Equal to comparison.

Syntax signature:col = val
Code snippet:
python
SELECT * FROM users WHERE status = 'active';
Expected Output:Matching rows.
Remember: Always ensure correct syntax formatting when calling =.
!=
Return: Value

Not equal to comparison.

Syntax signature:col != val
Code snippet:
python
SELECT * FROM users WHERE status != 'deleted';
Expected Output:Non-matching rows.
Remember: Always ensure correct syntax formatting when calling !=.
<
Return: Value

Less than comparison.

Syntax signature:col < val
Code snippet:
python
SELECT * FROM products WHERE price < 10.0;
Expected Output:Cheap items.
Remember: Always ensure correct syntax formatting when calling <.
>
Return: Value

Greater than comparison.

Syntax signature:col > val
Code snippet:
python
SELECT * FROM products WHERE price > 100.0;
Expected Output:Premium items.
Remember: Always ensure correct syntax formatting when calling >.
>=
Return: Value

Greater than or equal to comparison.

Syntax signature:col >= val
Code snippet:
python
SELECT * FROM employees WHERE age >= 21;
Expected Output:Adult employees.
Remember: Always ensure correct syntax formatting when calling >=.
<=
Return: Value

Less than or equal to comparison.

Syntax signature:col <= val
Code snippet:
python
SELECT * FROM employees WHERE age <= 18;
Expected Output:Minor employees.
Remember: Always ensure correct syntax formatting when calling <=.
AND
Return: Value

Combine conditions where all must be true.

Syntax signature:cond1 AND cond2
Code snippet:
python
SELECT * FROM users WHERE age > 21 AND status = 'active';
Expected Output:Active adult users.
Remember: Always ensure correct syntax formatting when calling AND.
OR
Return: Value

Combine conditions where at least one must be true.

Syntax signature:cond1 OR cond2
Code snippet:
python
SELECT * FROM users WHERE status = 'new' OR status = 'active';
Expected Output:Matching users.
Remember: Always ensure correct syntax formatting when calling OR.
NOT
Return: Value

Negate a condition.

Syntax signature:NOT condition
Code snippet:
python
SELECT * FROM users WHERE NOT status = 'suspended';
Expected Output:Non-suspended users.
Remember: Always ensure correct syntax formatting when calling NOT.
IN
Return: Value

Check membership within list.

Syntax signature:col IN (val1, val2)
Code snippet:
python
SELECT * FROM users WHERE region IN ('US', 'UK', 'CA');
Expected Output:Users in US, UK, or CA.
Remember: Always ensure correct syntax formatting when calling IN.
BETWEEN
Return: Value

Check if value falls in range inclusive.

Syntax signature:col BETWEEN lower AND upper
Code snippet:
python
SELECT * FROM products WHERE price BETWEEN 10.0 AND 50.0;
Expected Output:Products within range.
Remember: Always ensure correct syntax formatting when calling BETWEEN.
LIKE
Return: Value

Pattern match strings with wildcards % and _.

Syntax signature:col LIKE pattern
Code snippet:
python
SELECT * FROM users WHERE email LIKE '%@gmail.com';
Expected Output:Gmail users.
Remember: Always ensure correct syntax formatting when calling LIKE.
IS NULL
Return: Value

Check for missing/null value.

Syntax signature:col IS NULL
Code snippet:
python
SELECT * FROM orders WHERE ship_date IS NULL;
Expected Output:Unshipped orders.
Remember: Always ensure correct syntax formatting when calling IS NULL.
IS NOT NULL
Return: Value

Check for non-null value.

Syntax signature:col IS NOT NULL
Code snippet:
python
SELECT * FROM orders WHERE ship_date IS NOT NULL;
Expected Output:Shipped orders.
Remember: Always ensure correct syntax formatting when calling IS NOT NULL.
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