SQL Error Handling Examples

Implement TRY...CATCH in SQL Server

Write a SQL Server stored procedure that inserts a record and uses TRY...CATCH to handle any errors, returning a custom error message.

Expected output: Procedure inserts record or returns error message without failing.

Hint: Use BEGIN TRY and BEGIN CATCH blocks and ERROR_MESSAGE() function.

Create MySQL Procedure with Error Handler

Create a MySQL stored procedure that inserts a user and uses DECLARE HANDLER to catch duplicate key errors and return a friendly message.

Expected output: Procedure inserts user or returns duplicate username message.

Hint: Use DECLARE CONTINUE HANDLER FOR error code 1062.

SQL Server uses TRY...CATCH blocks to handle errors. Code in the TRY block executes normally, but if an error occurs, control passes to the CATCH block where error information can be accessed and handled.

DECLARE HANDLER in MySQL defines a block of code to execute when a specified error or condition occurs, allowing graceful error handling within stored procedures.

Error handling ensures that database operations do not leave data in an inconsistent state, helps provide meaningful error messages, and supports debugging and maintenance.