Selecting a suitable Recovery model for SQL Server

Microsoft SQL Server offers three recovery models namely simplify recovery planning, simply backup and recovery procedure and clarify compromises made over operational requirements. All three of these models resolve varied needs of performance, disk and tape space and offer shield for possible data loss. Each model offers something different than the other and therefore, while choosing the recovery mode, you must think about the compromises made between the following business operational requirements:

• Performance of large-scale operation for example: index creation or bulk loads

• Data loss exposure, for example: loss of committed transactions

• Transaction of log space consumption

• Simplicity of backup and recovery processes

Owing to the operations that you wish to execute, you can select more than one recovery models. After selection of an ideal recovery model or models, take required backups and plan the recovery processes. When a database is created, it has the same recovery model as of the original database. Mentioned below is detailed information over the recovery modes for SQL Server:

Simple Recovery: Simple Recovery model requires least administration than the rest two. In this recovery mode, only the most recent full database or differential backup data is recoverable. Minimal transaction log space is used, transaction log backups are not used and once the log space is not required for recovery from server failure, it gets reused. Although, the simple recovery model can be easily managed as compared to other two but only at the cost of higher data loss possibility if a data file is damaged.

Note: Simple Recovery mode is not suggested for production systems where loss of recent changes is unacceptable.

While using Simple Recovery, make sure that the backup interval is long enough to keep the backup overhead from affecting production work, yet short enough to prevent loss of vital information.

Simple Recovery allows high performance bulk copy operations and reclaims log space to keep space requirements small. In order to ensure there is no data loss, changes of the recent database or differential backup must be redone. It can recover to the end of any backup and then the changed must be redone.

Full and Bulk-Logged Recovery: The full recovery and bulk-logged recovery models offer greatest protection for data. These models rest over the transaction log to offer ability to recover and prevent work loss on a wider aspect of failure condition.

Full Recovery model offers flexibility of recovering databases to an earlier point-in-time. The Bulk-logged model offers high performance and lower log space consumption for certain large-scale operations. It does this at the expense of some flexibility of point-in-time recovery. Since many databases undergo periods of bulk-loading or index creation, you may require switching from Bulk-logged and Full recovery models.

During the Full Recover, no work is lost due to damaged data file and can recover an arbitrary point-in-time. Bulk-logged recovery permits high-performance bulk copy operations and minimal log space is used by bulk operations. There is no work loss exposure in Full recovery and if the log is damaged, changes since the most recent log backup must be redone.

In Bulk-logged recovery, if the log is damaged or bulk operations occurred since the most recent log backup, changes since the last backup are redone. Usually there is not work lost.

On the basis of above description, select the recovery models that you feel is ideal for your requirement and ensure that you don’t lose on vital information.Free Download Demo Version of Kernel for SQL Recovery Software to Recover SQL Server Database.

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