The recovery model is one of the essential attributes of an SQL Server database through which it is possible to understand how log changes are covered and how in the best angle restoration of data is possible in case of failure. Effectively, the recovery model determines the types of backup methods that can be employed and the level of data protection that is created through the control the application provides to transaction log handling. There are three main recovery models in SQL Server:

• Simple Recovery Model 
• Full Recovery Model 
• Bulk-Logged Recovery Model 

Thus, each model was designed for certain scenarios and objectives considering the data recovery requirements, performance characteristics, and storage presuppositions of particular businesses. This means that the right choice depends on factors such as the criticality of the database, data performance needs, and how much data loss the database is willing to allow. 

1. Simple Recovery Model 

The Simple Recovery Model is meant for databases that it is okay for the data on them to be lost between backups. In this model, the data in the databases are written to disk; the Transaction Log is truncated by the SQL Server as soon as the Check pointing process occurs and hence the Transaction Log does not contain logs for long-term backup. This means that the approach is compact concerning storage and decreases administration costs but does not allow executing point-in-time recovery (undeleting the database and returning it to a specific time).

Use Case: This model is best suited for databases that are not business-critical such as logs, or data that can easily be regenerated. 

2. Full Recovery Model 

The Full Recovery Model provides the best data protection when compared to other models. This model contains full transaction logging capability through which a point-in-time recovery technique can be employed. This is made possible by using the full backup together with the transaction backup whereby the database can be restored at any time since the last full backup. However, the trade-off is that it subjects the transaction log to more frequent backups to contain log file size which is also a performance-influencing factor. 

Use Case: Full recovery is most useful when applied to organizations’ most important databases that have no tolerance for data loss. For example, databases containing financial or health-care records in which every transaction needs to be logged and point-in-time recovery is mandatory. 

This model falls in the advanced backup and restore strategies, and is particularly relevant for businesses that cannot afford to have significant downtimes, and in which data backups need to be recoverable to the ‘t’. 

3. Bulk-Logged Recovery Model 

The last one, the Bulk-Logged Recovery Model is a mix of the simple and full models. It gives benefits of point-in-time recovery that are provided by traditional backup strategies and at the same time it is better in terms of logging for bulk processes like bulk insert, update, or delete. Rather than logging every transaction made, it logs the entire bulk operation as a single instance thus minimizing the size of the transaction log and also increasing the rate of data modification during large transactions. 

Nonetheless, recovery may be restricted if some insurmountable mass operation takes place and the transaction log is injured. This model is ideal to work with when there are many numbers of data that are processed but not always does logging reach its full measure. 

Use Case: Best used for databases that do more bulk operations with their large datasets, for instance, data warehouses or systems that should perform well when data is being loaded. 

Choosing the Right Model 

Choosing the right recovery model depends on the requirements that one needs for data recovery, the performance of the database, and the size of the database. Here are some guidelines: 

• Simple Recovery Model: Suitable for low-risk applications where data backup is not required to be consistent with a specific point in time. 
• Full Recovery Model: Use it where the ultimate availability of data in case of disaster is unbearable as well as point of time recovery is mandatory. 
• Bulk-Logged Recovery Model: Most suitable for situations when high performance during the most frequent and large-scale activities must be achieved, while at the same time, point-in-time recovery has to take place for the restless frequent and small-scale operations. 

There are usually switches in recovery models with the administration of more than one form of recovery model for a particular database. 

In simple words, SQL Server provides the opportunity to change the recovery model of the database using just one SQL statement. For example, to switch a database to the Full Recovery Model: 

It is fundamental to ensure that once the backup strategy has been set, it should be followed by a consistent regime of full, differential as well as transaction log backups. This will help you to make sure that you create a database that can be recovered easily for any time lost in a>particular period and also to control the volume or size of the transaction log. 

Conclusion 

Learning the various recovery models in SQL Server is quite informative to the administrators in choosing the right recovery model that best fits the needs of the organization regarding data recovery, performance of the system, and how resources are utilized. Even though you are working with complex mission-critical applications or multibillion records data warehousing applications, the recovery model, as well as the efficient backup model, determine the data reliability and potential loss time.