Test index key order with equality, range, and OR predicates, then use seek predicates and logical reads to choose the lead column.
SQL SERVER – Initializing the FallBack Certificate Failed With Error Code: 1, State: 20, Error Number: 0
After a service account password change, SQL Server would not start: Initializing the FallBack certificate failed, error code 1. Here is the fix.
Does Sort Order in Index Column Matters for Performance? – Interview Question of the Week #199
Does the sort order in an index column matter for performance? Yes, in some specific scenarios, and here is an example from a recent Health Check question.
SQL SERVER – How to Escape a Single Quote in SQL Server?
In my earlier post on “How to Escape a Single Quote in SQL Server? – Interview Question of the Week #192 I showed you a method of escaping a single quote.
SQL SERVER – AlwaysOn – Queries Waiting for HADR_AR_CRITICAL_SECTION_ENTRY
After a Windows cluster briefly lost quorum, a client’s AlwaysOn queries got stuck waiting for HADR_AR_CRITICAL_SECTION_ENTRY. Here is how we fixed the wait.
SQL SERVER – Cluster Resource ‘AGName’ of type ‘SQL Server Availability Group’ in Clustered Role ‘AGName’ Failed
Configuring an availability group is easy; trouble starts when the cluster breaks. Here I fix a failed cluster resource of type SQL Server Availability Group.
SQL SERVER – Script level upgrade for database ‘master’ failed because upgrade step msdb110_upgrade.sql encountered error 926, state 1, severity 25
An upgrade failed: Script level upgrade for database ‘master’ failed because upgrade step msdb110_upgrade.sql encountered error 926. I explain the cause and the fix.