How to repair database corruption from backup?

All we need is an easy explanation of the problem, so here it is.

I am learning about dbcc checkdb and that it detects corruption.

Suppose checkdb results show corruption in db.

What is the way to fix the corruption suppose I have the db backup?

How to solve :

I know you bored from this bug, So we are here to help you! Take a deep breath and look at the explanation of your problem. We have many solutions to this problem, But we recommend you to use the first method because it is tested & true method that will 100% work for you.

Method 1

You don’t repair it using the backup. You restore from a prior backup which is clean. I.e., the basics are, after detecting the corruption:

  1. Perform the last log backup if possible, make sure that no-one is doing further modifications in the database.
  2. Restore from a clean full backup
  3. Restore from a subsequent clean diff backup, if you have such.
  4. Restore an unbroken chain of log backups, if you have such, including the very last one you took in step 1.

You hopefully now have a clean database. Of course there are a lot of aspects around this (doing root cause analysis, etc). Brent Ozar has written a great blog post on this that I highly recommend: https://www.brentozar.com/archive/2016/05/dbcc-checkdb-reports-corruption/

Note: Use and implement method 1 because this method fully tested our system.
Thank you 🙂

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

Leave a Reply