In what sense? The word 'truncate' is used in more than one place with more than one meaning.
If you're referring to the transaction log, please read through this - Managing Transaction Logs[/url], and post any specific questions you may have afterwards.
If you're referring to something other than the transaction log, can you give some context and details to your question please.
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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