Running Under Compatibility Level 80

Hi There,
After we migrate our SQL 2000 databases, the compatibility level is set
to "SQL Server 2000(80)" by default. My question are:
1. What are the differences in terms of performance runing databases
under comp level 80 and comp level 90 in SQL 2005 ?
2. What do I lose if the database is still running under Comp level 80?
3. What do I gain by chaning to 90, what are things need to be
considered?
ThanksHi Don,
Check out the matrices in the BOL topic for sp_dbcmptlevel. Just changing
the compatibility level may not significanty change the performance, but the
use of feature that are not available because of it, could have a significan
t
impact.
John
"Don" wrote:

> Hi There,
> After we migrate our SQL 2000 databases, the compatibility level is set
> to "SQL Server 2000(80)" by default. My question are:
> 1. What are the differences in terms of performance runing databases
> under comp level 80 and comp level 90 in SQL 2005 ?
> 2. What do I lose if the database is still running under Comp level 80?
> 3. What do I gain by chaning to 90, what are things need to be
> considered?
> Thanks
>sql