SQL Server Database Recovery Models

SQL Server provides three recovery models to control the data protection and transaction log management in a database:

Simple Recovery Model: In this recovery model, the transaction logs are automatically truncated after each transaction checkpoint and don't support point-in-time recovery. This recovery model is suitable for small databases where data loss is acceptable. 

Example:

ALTER DATABASE [database_name] 

SET RECOVERY SIMPLE

Full Recovery Model: In this recovery model, the transaction logs are not automatically truncated and the entire transaction history is retained until a log backup is taken. This recovery model supports point-in-time recovery and is suitable for large databases with a high level of data protection. 

Example:

ALTER DATABASE [database_name] 

SET RECOVERY FULL

Bulk-Logged Recovery Model: In this recovery model, some types of bulk operations (e.g. bulk import) are minimally logged and the transaction logs are not automatically truncated. This recovery model is a middle ground between simple and full recovery models and is suitable for large databases with a moderate level of data protection. 

Example:

ALTER DATABASE [database_name] 

SET RECOVERY BULK_LOGGED

Note - It's important to choose the appropriate recovery model for a database based on the data protection and performance requirements.

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