Trust Coding : Programming: 🔍 Lab 2.2 : AND, OR, IN, BETWEEN, LIKE, IS NULL

🔍 Lab 2.2: SQL Filtering — AND, OR, IN, BETWEEN, LIKE, IS NULL

In this lab, you will learn how to filter data in SQL using advanced condition operators: AND, OR, IN, BETWEEN, LIKE, and IS NULL. We will use a sample employee table with Bangladeshi names.

📁 Sample Employees Table

ID	First Name	Last Name	Department	Salary	Email
201	Rakib	Hasan	IT	70000	rakib@company.com
202	Tamanna	Sultana	HR	55000	tamanna@company.com
203	Imran	Ahmed	Sales	72000
204	Sharmin	Jahan	Marketing	60000	sharmin@company.com
205	Naeem	Islam	IT	NULL	naeem@company.com

🧪 SQL Practice Queries with Explanation

1. AND – Filter by Department and Salary

SELECT * FROM employees
WHERE department = 'IT' AND salary > 60000;

This shows employees who are in IT department and have salary above 60,000.

2. OR – Either Department is HR or Salary below 60,000

SELECT * FROM employees
WHERE department = 'HR' OR salary < 60000;

Returns anyone from HR or anyone earning less than 60,000.

3. IN – Match Any Value from a List

SELECT * FROM employees
WHERE department IN ('HR', 'Sales');

Shows employees who are either in HR or Sales departments.

4. BETWEEN – Salary Between 55000 and 70000

SELECT * FROM employees
WHERE salary BETWEEN 55000 AND 70000;

Returns employees whose salary is in the range 55,000–70,000 inclusive.

5. LIKE – Name Starting with 'Sh'

SELECT * FROM employees
WHERE first_name LIKE 'Sh%';

Finds all employees whose first name starts with "Sh", such as "Sharmin".

6. IS NULL – Email Field is Empty

SELECT * FROM employees
WHERE email IS NULL;

Returns records where the email is missing (NULL).

📌 Summary

AND – Both conditions must be true
OR – Either condition can be true
IN – Match against multiple values
BETWEEN – Check if value is in a range
LIKE – Pattern matching (use % for wildcard)
IS NULL – Checks if a value is missing

✅ These SQL operators are essential for real-life data filtering. Practice them regularly to sharpen your SQL query skills.

Trust Coding : Programming

🔍 Lab 2.2 : AND, OR, IN, BETWEEN, LIKE, IS NULL