SQL server issue and solution
Troubleshooting Tips for Seamless SQL Server Transactional Replication
Introduction:
Transactional Replication is a powerful High availability feature in SQL Server that allows the consistent and near real-time distribution of data across multiple servers. However, like any complex system, it can cause issues that may disrupt the Replication process. In this blog, we will explore some common issues associated with Transactional Replication and provide practical resolutions. These troubleshooting tips are versatile, designed to support various SQL Server versions regardless of whether we are working with SQL Server 2012, 2016, 2019, or other supported SQL Server versions.
Issue 1: Error 20598 – The row was not found at the Subscriber when applying the replicated command.
Resolution: This error occurs when the row to be updated or deleted is not found at the subscriber. To resolve this issue, these are the steps to be followed:
- Verify the schema and table structure: Ensure that the schema and table structure at the subscriber match those at the publisher.
- Check for conflicts: Identify any conflicts that may prevent the row from being updated or deleted. Conflicts can occur if there are triggers, constraints, or other factors preventing the operation.
- Validate the data: Confirm that the data at the subscriber is consistent with the publisher. Use SQL Server Management Studio (SSMS) to compare data between the publisher and subscriber.
Issue 2: Latency in Replication
Resolution: Latency or the delay between changes at the publisher and their application at the subscriber, can be caused by various factors. To address latency:
- Monitor network performance: Ensure that the network between the publisher and subscriber is functioning optimally. Use tools like SQL Server Profiler to identify any network-related bottlenecks.
- Tune the Distribution agent: Adjust the frequency of the distribution agent to meet replication requirements. Consider optimizing the agent parameters and settings for improved performance.
- Check for long-running Transactions: Identify and address any long-running transactions at the publisher that may be delaying replication. Use the sys.dm_exec_sessions and sys.dm_tran_active_transactions DMVs to investigate.
Conclusion: Transactional Replication is a robust mechanism for maintaining consistent data across SQL Server instances. However, understanding and resolving common issues is crucial for ensuring the reliability and performance of replication. By following the suggested resolutions for the issues mentioned, we can troubleshoot and overcome challenges in SQL Server Transactional Replication setup.
