Database Recovery

Why SQL Server Returns NULL Info About Drives?

When you are trying to get information about drives on your server you might see that SQL is returning NULL values instead of actual values. In this article, we will understand the reason for such NULL values and how to prevent those. Dynamic management function sys.dm_os_volume_stats is a SQL Server dynamic management function with which you can get your server’s volume information attributes of server’s drives status of free space This dynamic management function requires...

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Why You Are Not Able to Access Database in an Availability Group in SQL Server?

Failover Condition Level determines when a failover should occur. This applies to SQL Server Always on Availability Group and to the SQL Server Failover Cluster Instances. Based on the failover condition level, you might not be able to access databases participating in Always On. Policy to failover For an availability group, automatic failovers are controlled by failover policy. With these policies, we can attain the highest level of control on the conditions that trigger a failover. In your...

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Message Handling Can Affect Your Availability Group Replicas in SQL Server

The state of databases participating in Always On are prone to change due to message handling. A sudden failover might interrupt a large transaction happening in the database that participates in Always On. This will result in a lengthy undo process and database status would be ‘Not Synchronizing’. Error message but no user action needed If your availability group is having hundreds of databases and heavy workload runs on the availability group, a sudden failover will change the status of...

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