should a db in simple recovery mode have logs truncated prior to backup, after backup or not at all?

should a sql server db in simple recovery mode have logs truncated prior to backup, afte开发者_如何学Cr backup or not at all?

In simple recovery mode, your transaction log won't grow larger than the amount of log space required by your largest concurrent transactions. Therefore in a well-behaved system, there is no need to truncate the log on each backup.

However, if there is a chance that some expensive (perhaps ad-hoc) queries will use a lot of log space, you might recover some disk space by truncating the log occasionally.