Depends.
What do you need them for, and what are your audit needs?
If you don't care about changes to rows, don't use them.
If you need to know what changed, then they're not adequate.
If you just need to know when a row changed, then use a modified date.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
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