SQL WHERE Clause – Complete Guide with Examples (2026-27)

✅ What is the SQL WHERE Clause?

The SQL WHERE clause is used to filter records in a query. It tells the database to return only the rows where the given condition is true. Without a WHERE clause, a SELECT query returns all rows from the table.

The WHERE clause can be used in:

• SELECT — to filter which rows to read
• UPDATE — to filter which rows to change
• DELETE — to filter which rows to remove

✅ SQL WHERE Clause – Basic Syntax

SELECT column1, column2, ...
FROM table_name
WHERE condition;

✅ SELECT:- Specifies the columns you want to retrieve.

✅ FROM:- Specifies the table to query.

✅ WHERE:- Specifies the condition that rows must meet to be returned.

✅ SQL WHERE Clause – Operators Reference Table

You can use the following operators inside a WHERE clause to build filter conditions:

✅ Example 1 – Filter by Country (= operator)

The Customers table below has records from different countries. We want only customers from the USA.

✅ SELECT Query:-

SELECT *
FROM Customers
WHERE Country = 'USA';

✅ Result:-

✅ Example 2 – Filter by Price (> operator)

Retrieve products that cost more than 50.

✅ SELECT Query:-

SELECT ProductName, Price
FROM Products
WHERE Price > 50;

✅ Result:-

✅ Example 3 – Filter Employees by Department

Select employees from the IT department only.

✅ SELECT Query:-

SELECT Name, Department
FROM Employees
WHERE Department = 'IT';

✅ Result:-

✅ Example 4 – Filter by Date Range (BETWEEN)

The BETWEEN operator returns rows where a value falls within a specified range — including both endpoints.

✅ SELECT Query:-

SELECT *
FROM Orders
WHERE OrderDate BETWEEN '2025-02-01' AND '2025-11-30';

✅ Example 5 – Pattern Matching with LIKE

The LIKE operator is used for pattern matching in text columns. Use % to match any number of characters and _ to match exactly one character.

✅ SELECT Query – Names starting with 'P':-

SELECT Name FROM Employees
WHERE Name LIKE 'P%';

✅ SELECT Query – Names containing 'mod':-

SELECT Name FROM Employees
WHERE Name LIKE '%mod%';

✅ Example 6 – Combining AND & OR Conditions

Use AND when all conditions must be true. Use OR when any one condition is enough.

✅ SELECT Query – AND example:-

SELECT * FROM Employees
WHERE Department = 'IT' AND Salary > 50000;

✅ SELECT Query – OR example:-

SELECT * FROM Employees
WHERE Department = 'IT' OR Department = 'HR';

✅ SELECT Query – Combined AND + OR with parentheses:-

SELECT * FROM Employees
WHERE (Department = 'IT' OR Department = 'HR')
AND Salary > 50000;

✅ Example 7 – Filter Employees Hired After 2025

✅ SELECT Query:-

SELECT *
FROM Employees
WHERE HireDate > '2025-01-01';

✅ Common SQL WHERE Clause Mistakes to Avoid