SQL Server: Unexpected 'Arithmetic overflow' scenarios When Using CAST in a Stored Procedure
I've hit a wall trying to I'm working on a personal project and I have a stored procedure in SQL Server 2019 that processes financial transactions... Occasionally, I encounter an 'Arithmetic overflow' behavior when executing a particular calculation. The procedure takes in a decimal value as an input and attempts to cast it to a different decimal type to perform rounding. Here's the relevant part of the code: ```sql CREATE PROCEDURE ProcessTransaction @TransactionAmount DECIMAL(18, 6) AS BEGIN DECLARE @RoundedAmount DECIMAL(10, 2); SET @RoundedAmount = CAST(@TransactionAmount AS DECIMAL(10, 2)); -- further processing... END ``` The input `@TransactionAmount` can sometimes exceed 99999999.999999, which I believe is causing the overflow when I attempt to cast it to `DECIMAL(10, 2)`. I tried to change the size of the `@RoundedAmount`, but that doesn’t seem to help. While debugging, I printed the value of `@TransactionAmount` right before the cast: ```sql PRINT @TransactionAmount; ``` And sure enough, when it prints a value larger than what `DECIMAL(10, 2)` can handle, the behavior occurs. I want to ensure that the casting won’t unexpected result, and ideally, I’d like to keep the values accurate. What are some best practices for handling this kind of situation without running into overflow errors while maintaining the integrity of my calculations? Should I consider changing the precision or using a different data type altogether? Any suggestions would be greatly appreciated. I'm working on a web app that needs to handle this. What am I doing wrong? For context: I'm using Sql on Ubuntu. How would you solve this?