Pulling Non-Clustered Index Data

Kenneth Fisher shows using a non-clustered index potentially to reconstruct corrupted data on a clustered index:

So why would you want to do this? Well lets say for example you have a table in a database where the clustered index has become corrupted. Let’s further say that no one mentioned this to you for .. say a year. (No judging!) So your only option at this point might be to use the REPAIR_ALLOW_DATA_LOSS of DBCC CHECKDB. But when you are done how much data has actually been lost? Can you get any of it back?

If you’ve lived a good life and are very lucky, you might recover all data this way.  Otherwise, it’s a good idea to run CHECKDB more frequently and check those backups regularly as well.

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