I recently repaired a single corrupt page in one of the tables in a 70gb database.
I had a backup which included the data contained in the page so I went about using DBCC CHECKDB with REPAIR_ALLOW_DATA_LOSS. I then transferred the rows from the old database back to the newly repaired database.
After running a DBCC CHECKDB WITH NO_INFOMSGS to make sure everything was okay again I then ran a full backup. The backup is 10gb less than the previous backups (like the one I took before the repair with CONTINUE_ON_ERRORS).
What is the reason for this? Does the DBCC repair do any reordering of pages which would recover space or something similar? Table sizes look similar to previous but I'm a little worried there could be missing data.
Best Answer
When you transferred data, you probably compacted data by an implied index rebuild.
Or the REPAIR_ALLOW_DATA_LOSS lived up to it's name...