How do I NTH select in Paradox?

#1

Hello all,

How can I ramdomly select a list of records from an existing table?

For example: 500,000 names divided by 20,000 samples = 25. The N is
25, meaning samples would be sent to every 25th name on the list.

Any help will be appreciated?

TIA

ja

#2

If you know, for example, that you want every 25th record then scan the
table and use a counter. Every time it hits 25 copy the record you are
on or the parts you need, reset the counter and keep scanning. When it
hits 25 again, grab that, reset and keep scanning.

Denn Santoro
President
Resource Development Associates
http://www.RDAWorldWide.Com
Offices in the United States and Germany
Providing solutions to health care, business, governments and
non-profits since 1982

#3

Or use a 'step 25' in the scan, after determining the step.

--

Tony McGuire
"It's not about having enough time. It's about priorities."
___________________________

#4

ja wrote:

Quote:

How can I ramdomly select a list of records from an existing table?

For example: 500,000 names divided by 20,000 samples = 25. The N is
25, meaning samples would be sent to every 25th name on the list.

Do you really want random or just every 25th? I wrote a long time ago
that makes it easy to generate a randomly selected data set. Let me
know if you want a copy. If you just want every 25th, go with what
Dennis and Tony said.

#5

Quote:

The N is
25, meaning samples would be sent to every 25th name on the list.

I doubt that this would qualify as "random" from statistical point of view,
but maybe good enough in the situation.

Anders

#6

I want to ramdomly select 183,000 records from a 3,002,451 record
table. Yes, I would like a copy of your code.

TIA

On Mon, 13 Feb 2006 12:10:03 -0800, Ed Nash <ask.me (AT) specifically (DOT) pls>
wrote:

Quote:

ja wrote:

How can I ramdomly select a list of records from an existing table?

For example: 500,000 names divided by 20,000 samples = 25. The N is
25, meaning samples would be sent to every 25th name on the list.

Do you really want random or just every 25th? I wrote a long time ago
that makes it easy to generate a randomly selected data set. Let me
know if you want a copy. If you just want every 25th, go with what
Dennis and Tony said.

#7

Anders, very well pointed out. My example does not qualify as a
'ramdom selection.' Do you have any written code that does ramdom
selection for large tables(3 million recs)? If you do, would post it?

On Mon, 13 Feb 2006 21:42:47 +0100, "Anders Jonsson"
<gt3TakeThisAway (AT) bredband (DOT) net> wrote:

Quote:

The N is
25, meaning samples would be sent to every 25th name on the list.

I doubt that this would qualify as "random" from statistical point of view,
but maybe good enough in the situation.

Anders

#8

"Ed Nash" <ask.me (AT) specifically (DOT) pls> wrote in message

Quote:

I wrote a long time ago that makes it easy to generate a randomly
selected data set.

"easily generated" does not necessarily mean it qualifies as "random"..
depending on the reason for the request, the legal requirement of "random"
could be *very* important.. it's been a while, but we've had some
discussions on this subject.. you might be quite surprised at the results..

--
Steven Green - Waldorf Maryland USA

Diamond Software Group
http://www.diamondsg.com/main.htm
Paradox Support & Sales - Corel CTech Paradox

Diamond Sports Gems
http://www.diamondsg.com/gemsmain.htm
Sports Memorabilia and Trading Cards

#9

ja wrote:

Quote:

I want to ramdomly select 183,000 records from a 3,002,451 record
table. Yes, I would like a copy of your code.

Check your email.

#10

"ja" <jouandae (AT) sbcglobal (DOT) net> wrote in message

Quote:

I want to ramdomly select 183,000 records from a 3,002,451 record table.

please tell us the reason for the "random" request.. most "random"
processors do not meet the legal requirement of "random", so your reason for
this has great bearing..

--
Steven Green - Waldorf Maryland USA

Diamond Software Group
http://www.diamondsg.com/main.htm
Paradox Support & Sales - Corel CTech Paradox

Diamond Sports Gems
http://www.diamondsg.com/gemsmain.htm
Sports Memorabilia and Trading Cards