Nth Record Selection in dBASE III

[Guest_imported]

I have several databases of names and addresses, totaling 150,000 names. I need to mail to one-tenth of the total count, but don't know how to do an "nth name" selection in dBASE. I'm quite willing to export to Excel if that will make a difference.

Thanks!

 

[MiggyD]

*the following 2 lines are pseudo memory variables
*you'll need to make your own as needed.
CustFName = " "
CustLName = " "

* THIS IS THE FIRST RECORD TO READ
MYCOUNT=1

CLEAR
USE (DATABASE TO USE HERE)
GO TOP
DO WHILE 0=0
IF EOF(DATABASE TO USE HERE) THEN EXIT DO
GOTO RECNO(MYCOUNT)
* HERE'S WHERE YOU STORE THE DATABASE RECORD'S FIELD'S VALUES
* TO THE MEMORY VARIABLES YOU HAVE MENTIONED ABOVE.
CustFName = (database field-ex "FirstName&quot
CustLName = (database field-ex "LastName&quot
? CustFName + CustLName
MYCOUNT = MYCOUNT + 10 * 150,000 / 10 = 15,000 RECS TO READ
IF MYCOUNT > RECCOUNT() THEN EXIT DO
LOOP
ENDDO
CLOSE DATABASES
EXIT

The above should work, I haven't tested it yet, but it should work.

Paste the above code to a TXT file then rename the TXT to PRG and run it using DBASE.

Hoped I helped.
--MiggyD
"It's mind over matter. They don't mind so you don't matter to them."

 

[Guest_imported]

Thanks! A friend suggested another option which also worked, but is not as elegant.

I created a numeric field called "N", and filled it with the record number. I created another numeric field called "REMAIND" and finally ran a routine using MOD, like so:

replace all n with recno()
replace all remaind with mod(n,10)

This put a single-digit number in REMAIND from 0 through 9. I could then COPY TO NEWFILE FOR REMAIND = 1 (or any other number I chose) to get a 1/10th selection. Crude, but it worked. The method outlined by MiggyD is a lot more clever because it allows the user to select any "n". I will use it next time. Again, thanks!

 

[GEMS]

Here's another solution that is similar to the "remainder" technique already suggested.
In the follwoing command, substitute CHOICE with the number you require - ie in your stated case - 10. The table is then restricted to that fraction ie a CHOICE of 10 gives a tenth - every tenth record, three gives a third - every third record etc.
SET FILTER TO INT(RECNO()/CHOICE)=RECNO()/CHOICE
With the filter set, you can then perform any operation on the restricted table.
Don't forget to reset the filter before the next operation.
Hope this helps

 

[MiggyD]

well I'm glad your friend suggested it. I would like to point out that by doing it that way, you will be essentially creating a !LARGER! database--you know, copying the existing structure and adding 2 MORE fields.

But, if the drive has plenty of room then go for it. But, if you are limited on space, it would be much easier to create say a 100 to 200 byte program than it is to copy a monster of a database and pray for no "Corrupt Database" signs.

I'm from the old school where we used the KISS :-X method as much as possible. Good luck in your endeavors.

--MiggyD : "It's mind over matter. They don't mind so you don't matter to them."