Andrew,
There's 2 options both requiring the addition of a new column (as float) to
your table that is then updated.
Version 1 is to update the new column with the rowid number thus:
Update Mytable Set Mycol = rowid
and then
Select * from Mytable where Mycol mod N into randsampl
where N is based on the number of records you want.
Version 2 is to update the new column with a random number thus:
Update Mytable Set Mycol = rnd(1)*79000
and then
Select * from Mytable where Mycol < 7900 into randsampl
for an approx 10% sample
Ian
>>> "Andrew Tracey" <[EMAIL PROTECTED]> 17/01/2006 08:15:56 >>>
I currently have a table with 79000 points in it. Does anyone have a query or
know how to pick out a random sample of the data (say every 100 or every 1000
records)
Thanks in advance
Andrew Tracey
Information Support Officer
Corporate Information
Corporate Development
South Tyneside Council
Westoe Road
South Shields
NE33 2RL
Tel: 0191 4247561
E-Mail : [EMAIL PROTECTED]
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