SQL IF Statement: Syntax, Usage, and Examples

The SQL IF statement lets you apply conditional logic to your queries and procedures. It helps you control what happens based on whether a condition is true or false. Whether you're updating data, controlling flow in stored procedures, or handling logic in a query, the IF statement SQL syntax gives you more flexibility.

How to Use the SQL IF Statement

The basic structure of the SQL IF statement depends on the context. You’ll find different variations based on whether you're writing a standalone statement, using IF in a stored procedure, or embedding it in a SELECT clause with CASE.

IF Statement in Stored Procedures (MySQL or SQL Server)

IF condition THEN
   -- do something
ELSE
   -- do something else
END IF;

IF...ELSE Syntax (T-SQL - SQL Server)

IF condition
   BEGIN
      -- true block
   END
ELSE
   BEGIN
      -- false block
   END

You can also use the SQL IF THEN statement in control-flow scenarios to execute blocks of code selectively.

Conditional Logic in Queries (via CASE)

Standard SQL doesn’t support standalone IF in queries. Instead, you use CASE to add conditional logic inside a SELECT statement.

SELECT name,
  CASE
    WHEN age >= 18 THEN 'Adult'
    ELSE 'Minor'
  END AS category
FROM users;

This approach allows you to mimic the behavior of an if else statement SQL query inside SELECT.

When to Use the SQL IF Statement

In Stored Procedures

Use the SQL IF statement when writing stored procedures or functions to execute specific blocks of code.

IF @role = 'admin'
   PRINT 'Access granted';
ELSE
   PRINT 'Access denied';

This logic can be expanded to include multiple layers of decision-making.

When Performing Data Validation

Validate inputs before executing operations.

IF EXISTS (SELECT * FROM users WHERE email = @email)
   BEGIN
      PRINT 'User already exists';
   END
ELSE
   BEGIN
      -- Insert new user
   END

This helps protect your database from duplicate or unwanted data.

Inside SQL Queries Using CASE

You can simulate the SQL IF statement using CASE to return values conditionally.

SELECT order_id,
  CASE
    WHEN total > 100 THEN 'High Value'
    ELSE 'Standard'
  END AS order_type
FROM orders;

The SQL IF THEN statement behavior is built into the CASE structure, giving you logic within result sets.

Examples of the SQL IF Statement

Using IF to Perform Conditional Inserts

In a stored procedure:

IF NOT EXISTS (SELECT * FROM products WHERE sku = '12345')
BEGIN
   INSERT INTO products (sku, name)
   VALUES ('12345', 'Wireless Mouse');
END

You check for a condition, and only act if it’s not met.

Using IF ELSE to Control Flow

IF @count > 10
   BEGIN
      PRINT 'Too many records';
   END
ELSE
   BEGIN
      PRINT 'Record count acceptable';
   END

This classic if else logic lets your SQL scripts react to different scenarios.

SQL Query with IF Statement via CASE

SELECT id, score,
  CASE
    WHEN score >= 90 THEN 'A'
    WHEN score >= 80 THEN 'B'
    ELSE 'C'
  END AS grade
FROM student_scores;

This is one of the most common uses of conditional logic directly inside SELECT statements.

Learn More About IF Statement in SQL

Nesting IF Statements

You can nest SQL IF statements to handle complex logic:

IF @status = 'pending'
   BEGIN
      IF @balance >= 100
         BEGIN
            UPDATE accounts SET status = 'approved' WHERE id = @id;
         END
      ELSE
         BEGIN
            PRINT 'Insufficient balance';
         END
   END

This lets you handle multiple conditions step-by-step.

SQL IF THEN Statement vs CASE

The SQL IF THEN statement works well for procedural logic—like branching inside stored procedures or functions. The CASE expression, on the other hand, works inside SQL queries.

When to use IF:

• In procedural SQL (stored procedures, functions)
• For branching execution (e.g. run or skip blocks of code)

When to use CASE:

• Inside SELECT, UPDATE, or ORDER BY clauses
• For returning conditional values

Use CASE for Output Formatting

Let’s say you want to add a label based on a price range:

SELECT name, price,
  CASE
    WHEN price < 50 THEN 'Budget'
    WHEN price BETWEEN 50 AND 100 THEN 'Mid-range'
    ELSE 'Premium'
  END AS price_category
FROM products;

This turns numerical data into something more readable and actionable.

IF in SQL Server vs IF in MySQL

In SQL Server:

• You use BEGIN...END to group multiple statements
• Variables are declared with @

In MySQL:

• Use DELIMITER to define stored procedures
• Use THEN and END IF; instead of BEGIN...END

The SQL IF statement syntax varies slightly across platforms, but the core idea remains consistent.

How to Combine Multiple Conditions

Use logical operators to test more than one condition:

IF @quantity > 10 AND @price < 50
BEGIN
   UPDATE products SET discount = 0.1 WHERE id = @product_id;
END

You can build complex logic with AND, OR, and NOT.

Simulating IF Statements Without Stored Procedures

Even if your environment doesn’t support stored procedures or blocks, you can simulate IF logic using CASE, COALESCE, or nested SELECT statements.

SELECT
  COALESCE(NULLIF(age, 0), 'Unknown') AS adjusted_age
FROM users;

While not technically an IF, this approach still adjusts values conditionally.

The SQL IF statement gives you fine-grained control over how your SQL code behaves. Whether you're running a stored procedure, applying logic inside a query, or validating inputs before performing updates, this feature makes your database scripts smarter and more adaptive.