Is there a function to randomly select certain percent of the data from a
table each time?

Not in SQL.  You really need to use a Stat package that can interface
with the RDBMS.  It will have all of the corrections that you need for
a proper sample.

What is a Stat Package?

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Statistical package -- SAS, SPSS, etc.

Not easily in 2000.  A trick is to do some thing like this would be
(assuming you want 25% of a 100 row table)

select top 25 *
from table
order by newid()

It doesn't give you all of the performance improvements of a proper sampling
function (since a sort will be required on a newly introduced value) but it
should give you all of the other characteristics.

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You could something like that

Select TOP 5
from Sometable
order by New_id()

HTH, Jens Suessmeyer.

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Sure,

Select TOP 25 Percent Col1, Col2,....
From Table
Where....
Order By...

The Order By statement is obviously key to returning the expected results.


Thomas

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