Backups

• Hugo Kornelis

  SSC Guru

  Points: 64790

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  November 17, 2014 at 12:53 pm

  #1759070

  navneet.agarwal19 (11/17/2014)

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  A Big confusion is there.

  F1 full backup

  T1 Log Backup

  D1 Differential Backup

  T2 Log Backup

  D2 Differential Backup

  T3 Log Backup

  F2 full backup

  T4 Log Backup

  D3 Differential Backup

  T5 Log Backup

  D4 Differential Backup

  T6 Log Backup

  Now If F2 is corrupt. To restore database, the sequence :

  F1, D4, T6

  or F1, D2, T3, T4, T5, T6

  I don't think F1, D3, T5, T6 works

  The first idea (F1, D4, T6) will not work. D4 is a differential for F2 and cannot be restored after F1.

  The second option (F1, D2, T3-T6) will work and is the correct restore sequence if F2 is corrupt.

  The sequence F1, D3, T5, T6 will not work for the same reason that F1, D4, T6 will not work - D3 is based off F2. But F2, D3, T5, T6 will work if D4 is corrupt.

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  Hugo Kornelis, SQL Server/Data Platform MVP (2006-2016)
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