SQL Server: best practices for Deadlock implementing Custom Retry Logic in Stored Procedures?
I'm working with frequent deadlocks in my SQL Server 2019 application, particularly during high load periods when multiple users are trying to update the same records simultaneously. To manage the deadlocks, I've implemented a custom retry logic in my stored procedures, but I'm not sure if I'm doing it correctly. The behavior I often see is `Transaction (Process ID 56) was deadlocked on lock resources with another process and has been chosen as the deadlock victim.` My current approach involves catching the deadlock behavior and retrying the update, but I'm still working with issues where the application hangs for too long or fails to update records after multiple retries. Here’s a simplified version of my stored procedure: ```sql CREATE PROCEDURE UpdateEmployeeSalary @EmployeeID INT, @NewSalary DECIMAL(10, 2) AS BEGIN DECLARE @RetryCount INT = 0; DECLARE @MaxRetries INT = 3; DECLARE @Success BIT = 0; WHILE @RetryCount < @MaxRetries AND @Success = 0 BEGIN BEGIN TRY UPDATE Employees SET Salary = @NewSalary WHERE EmployeeID = @EmployeeID; SET @Success = 1; END TRY BEGIN CATCH IF ERROR_NUMBER() = 1205 -- Deadlock behavior code BEGIN SET @RetryCount = @RetryCount + 1; WAITFOR DELAY '00:00:01'; -- Delay before retrying END ELSE BEGIN THROW; -- Rethrow the behavior if it's not a deadlock END END CATCH END END ``` I’m wondering if there are any best practices for handling deadlocks in SQL Server and whether there's a more efficient way to implement the retry logic. Are there any specific settings or configurations I should be aware of? Would it be better to use a transaction with a specific isolation level, or is there a better method to avoid these deadlocks in the first place? Any insights or improvements would be greatly appreciated!