Top 25 Customers Report

I am writing a routine in objectpal to get the top 25 customers into a table and subsequently a report. I can sort the table using "custTbl.attach" and "sort descending" like:

custTbl.attach("sortme.db")
sort custTbl
on ":PRIV:revenue" D
to ":PRIV:sorted.db"
endSort

But I need some form of TCursor loop or similar method to peel off the first (top) 25 customers.

I could not find a 'Top n' feature in Paradox Reports
Currently using Paradox 11 with sp2.
Any assistance or links to a solution appreciated.

This one is real easy.

var
darr dynArray[] anytype
tc tCursor
rev currency
endVar

; sort your table first as in your email

tc.open(":priv:sortme.db")
tc.moveToRecNo(25)
rev = tc."revenue"
darr["Revenue"] = ">=" + string(rev)
tc.setGenFilter(darr)
tc.copy(":PRIV:top25.db")

; that's it

*Slightly* different than Cliff's.

======================
movetorecno(), HELP
This method is recommended only for dBASE tables. If used for a Paradox table, moveToRecNo behaves exactly like the moveToRecord method.
======================

tc.movetorecord(min(25,tc.nrecords()))
Then do Cliff's stuff.

This way, if there are fewer than 25 records in the table, you are covered.

Also, you will probably want to open the table resulting from the copy and verify that there are only 25 records. You could have more than one with the exact 'revenue' value of that 25th record.

In case there are more than 25 after copy,

tc.open(":priv:top25.db")
if tc.nrecords()>25 then
  tc.edit()
  tc.movetorecord(26)
  while true 
    tc.deleterecord()
    if tc.recno()=25 then
      quitloop
    endif
  endwhile
  tc.endedit()
endif
tc.close()

> darr["revenue"] = ">=" +string(rev)

You might change this and try

darr["revenue"] = "not blank, >=" +string(rev)

Thinking about it further, I would change

tc.movetorecord(26)

to

tc.end()

No use flirting with where the tcursor winds up after a delete.

Thanks for the help Cliff & Montana, it's good to know there is help out there. The code works fine as you suggested and is giving me the result I needed. I did however try out adding a variable, so the end user can enter on the form, say the top 30 or 50 customers depending on what's required. I made it something like this:

method pushButton(var eventInfo Event)
var
custTbl Table
tv TableView
darr dynArray[] anytype
tc tCursor
rev currency
n String
endVar
n = qty
custTbl.attach("sortme.db")
sort custTbl
on "revenue" D
to "sorted.db"
endSort
tc.open("sorted.db")
tc.moveToRecNo(n)
rev = tc."revenue"
darr["revenue"] = ">=" +string(rev)
tc.setGenFilter(darr)
tc.copy("top25.db")
tv.open("top25.db")
endMethod

where "qty" is a field on the form. This worked fine as well, until I entered a value >=70 then the whole table was returned. It turned out that I only had values in 69 records for 'revenue' the rest being blank or no sales. I will now try incorporating Montana's loop to remove '>n'records.
Once again thanks for the assistance.

tried:
darr["revenue"] = "not blank, >=" +string(rev)
But it returned the whole table :-( I guess "not blank" does not work the same as in queries in this instance.
Overall though the primary objective has been achieved, thanks once again.