Handling errors in stored procedures

Whenever any SQL statement is executed, it either succeeds or fails. As an application developer, we need to make sure that we handle all possible errors gracefully. To ease this task, DB2 provides various tools or methods that can be used for better error handling.

There are two types of errors. If an SQL statement literally fails, then that's an error. However, there could be cases where the SQL statement passes technically but the results are not proper from a business point of view. For example, if we are updating salaries of employees in the Employee table and if the new salary becomes negative somehow, then technically the update was successful, but we all know that negative salary is not valid. So we need to handle such error cases as well in our code.

In this recipe, we will focus on methods that can be used for error handling in stored procedures.

How to do it...

Error handling in stored procedures is very similar to what we do in programming languages...