>>Metin,
>>
>>In SQL Server you can not create an index using a function. Use a date range when looking for a date, e.g.
>>

>>select * from myTable where DateField >=@Today and DateField < @Tomorrow
>>

>
>Thank you all,
>I'll use Naomi's way. I use in first variable today 00:00 and second variable today 24:59:59 . I'm afraid of about performance in other ways. I'm not sure if sql server will use index with other ways...

OK. I think you meant >= @today and < @today + 1. I am not afraid about performance in other (and possibly better) ways:) In other ways of course it would use the index because it finds just the index it wants - I assume by other ways you mean creating computed column and indexin on it:)
Cetin