If Else in SQL Server

Hello Dev! Are you looking for a comprehensive guide on the most commonly used conditional statement in SQL Server? Look no further because in this article, we will discuss everything you need to know about the If Else statement in SQL Server.

What is If Else statement in SQL Server?

The If Else statement is a conditional statement that allows you to execute a block of code if a certain condition is met, and another block of code if the condition is not met. This statement is used in various programming languages including SQL Server to enable developers to write complex queries that provide meaningful results.

Let’s dive deeper into what the If Else statement does and how it works in SQL Server.

If condition is true

If the condition specified in the If Else statement is true, the SQL Server engine will execute a set of statements under the If clause. Here is an example:

Employee Name	Salary
John	5000
Alice	6000

In the above example, if we want to select only those employees whose salary is greater than 5500, we can use the If Else statement in the following way:

If (select salary from employee where name='John') > 5500Select * from employee where name='John';ElseSelect 'Salary is not greater than 5500';

The above query will return the following result:

Employee Name	Salary
Alice	6000

If condition is false

If the condition specified in the If Else statement is false, the SQL Server engine will execute a set of statements under the Else clause. Here is an example:

If (select salary from employee where name='Mike') > 5500Select * from employee where name='Mike';ElseSelect 'Salary is not greater than 5500';

The above query will return the following result:

Result
Salary is not greater than 5500

FAQ

1. What is the difference between If Else and Case When statement in SQL Server?

While both If Else and Case When are conditional statements in SQL Server, they have different purposes. If Else is used when you need to execute one set of statements if a condition is true, and another set of statements if the condition is false. Case When, on the other hand, is used to evaluate multiple conditions and provide different results based on each condition.

2. Can I use If Else statement in a stored procedure?

Yes, If Else statement can be used in a stored procedure just like any other SQL statement.

3. Is If Else statement supported in all versions of SQL Server?

Yes, If Else statement is a standard SQL statement and is supported in all versions of SQL Server.

4. Can I use a nested If Else statement in SQL Server?

Yes, nested If Else statement can be used in SQL Server where one If Else statement is nested inside another If Else statement.

5. What are some common mistakes when using If Else statement in SQL Server?

Some common mistakes include incorrect syntax, not specifying the condition properly, and not providing the correct logic for each situation under the If Else clause.

Conclusion

Now that you have a better understanding of how to use If Else statement in SQL Server, you can write more complex queries that produce meaningful results. Remember to always double-check your syntax and logic to avoid common mistakes. Happy coding!