Rebuilding of indexes cause the transactional log file to grow

The index rebuild operation runs by default in a single long-running transaction, that prevents the Transaction Log space reuse while rebuilding a large index. Switching to the BULK_LOGGED recovery mode while doing an index rebuild operation will reduce the amount of transaction log generated. If you’re considering using the BULK_LOGGED recovery mode, beware that you... » read more

Hash Index

What is a ‘HASH INDEX’ in SQL? A Hash Index is a specific type of index that works best for equality comparisons. It uses a hash function to distribute rows evenly across a specified number of buckets. The hash function takes column values as input and returns a bucket number. When a query involving an... » read more

Recreating MSSQL Always On using SSMS AlwaysOn Wizard

Recreating Always On from an existing setup using SSMS AlwaysOn Wizard. Note: Delete all database and database files on secondary servers. Make sure all drive and folder mapping are the same as primary server. Use Local drive or NAS drive for AlwaysOn backup file location. Make sure existing database backup jobs has been disabled. Might... » read more

Restore Database from full, differential, and log backup files.

https://learn.microsoft.com/en-us/sql/relational-databases/backup-restore/restore-a-differential-database-backup-sql-server?view=sql-server-ver16 RESTORE WITH NORECOVERY which leaves the database non-operational, and does not roll back the uncommitted transactions. Additional transaction logs can be restored. The database cannot be used until it is recovered. Examples (Transact-SQL) A. Restoring a differential database backup This example restores a database and differential database backup of the MyAdvWorks database. B. Restoring a database, differential... » read more

Upgrade availability group replicas

https://learn.microsoft.com/en-us/sql/database-engine/availability-groups/windows/upgrading-always-on-availability-group-replica-instances?view=sql-server-ver16 When upgrading a SQL Server instance that hosts an Always On availability group (AG) to a new SQL Server version, to a new SQL Server service pack or cumulative update, or when installing to a new Windows service pack or cumulative update, you can reduce downtime for the primary replica to only a single... » read more

Things to Avoid in Your Query

LIKE ‘%xxxxxx%’ https://www.brentozar.com/archive/2010/06/sargable-why-string-is-slow/ Table Valued Functions https://www.brentozar.com/blitzcache/tvf-join/ Functions in from/below Implicit Conversions (convert to different data type) Comparing the contents of 2 columns on 1 table Table Variables Table variable does not have stats and serial for updates.