It's up to you but you're missing on such new features as UDF's, TOP clause in SELECT and so on. Check sp_dbcmptlevel topic in the BOL for more details.

>Interesting, it returned a value of 65.
>
>I guess I would be hesitant to change this value as it may impact
>other stored procs. The system was originally written in v 6.5 and converted to SQL2K about one year ago.
>
>>Check compatibility level using sp_dbcmptlevel. If it's last than 70 than empty string literal ('') is interpreted as a single blank. It also could affect some other commnads and behaviors.
>>
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